Patient interface

ABSTRACT

A patient interface for delivering breathable gas to a patient includes a nasal prong assembly including a pair of nasal prongs structured to sealingly communicate with nasal passages of a patient&#39;s nose in use and headgear to maintain the nasal prong assembly in a desired position on the patient&#39;s face. The headgear includes side straps and rigidizers provided to respective side straps. Each rigidizer includes a first end portion that provides a connector structured to engage a respective end of the nasal prong assembly and an inwardly curved protrusion in the form of a cheek support that curves inwardly of the connector. The cheek support is adapted to follow the contour of the patient&#39;s cheek and guide a respective end portion of the side strap into engagement with the patient&#39;s cheek to provide a stable cheek support.

CROSS-REFERENCE TO APPLICATION

This application claims the benefit of U.S. Provisional Application Nos.60/935,179, filed Jul. 30, 2007, 60/996,160, filed Nov. 5, 2007,61/006,409, filed Jan. 11, 2008, 61/064,818, filed Mar. 28, 2008, and61/071,512, filed May 2, 2008, and Australian Provisional ApplicationNos. AU 2008900891, filed Feb. 25, 2008, AU 2008900134, filed Jan. 11,2008, AU 2008900136, filed Jan. 11, 2008, AU 2008900137, filed Jan. 11,2008, AU 2008900138, filed Jan. 11, 2008, AU 2008900139, filed Jan. 11,2008, AU 2008900140, filed Jan. 11, 2008, and AU 2008900141, filed Jan.11, 2008, each of which is incorporated herein by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates to a patient interface for delivery ofrespiratory therapy to a patient. Examples of such therapies areContinuous Positive Airway Pressure (CPAP) treatment, Non-InvasivePositive Pressure Ventilation (NIPPV), and Variable Positive AirwayPressure (VPAP). The therapy is used for treatment of variousrespiratory conditions including Sleep Disordered Breathing (SDB) suchas Obstructive Sleep Apnea (OSA).

BACKGROUND OF THE INVENTION

Mask systems form an interface between a patient and apparatus providinga supply of pressurized air or breathing gas and are hence sometimesreferred to as patient interfaces. In this specification, the words masksystem and patient interface will be used interchangably. Mask systemsin the field of the invention differ from mask systems used in otherapplications such as aviation and safety in particular because of theiremphasis on comfort. This high level of comfort is desired becausepatients must sleep wearing the masks for hours, possibly each night forthe rest of their lives. Mask systems typically, although not always,comprise (i) a rigid or semi-rigid portion often referred to as a shellor frame, (ii) a soft, patient contacting portion often referred to as acushion, and (iii) some form of headgear to hold the frame and cushionin position. Mask systems often include a mechanism for connecting anair delivery conduit. The air delivery conduit is usually connected to ablower or flow generator.

A range of patient interfaces are known including nasal masks, nose &mouth masks, full face masks and nasal prongs, pillows, nozzles &cannulae. Masks typically cover more of the face than nasal prongs,pillows, nozzles and cannulae. In this specification, all will becollectively referred to as patient interfaces or mask systems. Nasalprongs, nasal pillows, nozzles and cannulae all will be collectivelyreferred to as nasal prongs.

SUMMARY OF THE INVENTION

A first aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. A mask system in accordance withan embodiment of the invention provides improved seal, fit, comfort,stability, adjustability and ease of use compared to prior art masksystems. Other aspects of the invention include providing a small,lightweight, unobtrusive mask system. Another aspect is to provide amask system that fits a wide range of different faces.

One aspect of improved seal is provided through the use of dual wallednasal pillows in accordance with an embodiment of the invention. Anotheraspect is the ability of a mask system in accordance with an embodimentof the invention to maintain a seal despite tube drag, side-sleeping,and other disruptions. Another aspect of improved seal and fit isthrough the adjustability provided by a mask in accordance with anembodiment of the invention which allows adjustment to better suit anindividual patient's face.

A mask system in accordance with an embodiment of the invention isflexible and can fit a wide variety of facial shapes. An aspect offlexibility of a mask system in accordance with an embodiment of theinvention is provided through the use of a semi-rigid frame. The use ofa semi-rigid frame also leads to an improved seal with an elbow, and areduction in the overall number of parts.

A mask system in accordance with an embodiment of the invention providesimproved comfort through improved seal, meaning patients do not need toovertighten headgear straps to get a seal. Another aspect of improvedcomfort comes from removal of a rear buckle when compared to otherwisesimilar prior art mask systems. Another aspect of the inventionproviding improved comfort is through the improved attachment mechanismof stiffening portions of the interface stabilizing arrangement, forexample, across the cheek regions. Another aspect of improved comfort ofthe present invention results from a more comfortable strap and orpadding arrangement in the cheek region that leads to a reduction in“cheek mark” when compared to the prior art.

An aspect of improved stability provided to a mask in accordance with anembodiment of the invention is through support features that engage withthe front of the face generally in the region of the maxilla and orzygoma, depending on the size of the patient's face.

An aspect of the present invention relates to a patient interfaceincluding a nasal prong assembly including a pair of nasal prongsstructured to sealingly communicate with nasal passages of a patient'snose in use and headgear to maintain the nasal prong assembly in adesired position on the patient's face. The headgear includes sidestraps and rigidizers provided to respective side straps. Each rigidizerincludes a first end portion that provides a connector structured toengage a respective end of the nasal prong assembly and a curvedprotrusion in the form of a cheek support that curves forward of theconnector. The cheek support is adapted to follow the contour of thepatient's cheek and guide a respective end portion of the side strapinto engagement with the patient's cheek to provide a stable cheeksupport.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. The patient interface includes anasal seal to sealingly communicate with the patient's nose in use andheadgear to maintain the nasal seal in a desired position on thepatient's face. The headgear includes side straps. Each side strapincludes a curved protrusion in the form of a cheek support adapted tofollow the contour of the patient's cheek and guide a respective endportion of the side strap into engagement with the patient's cheek toprovide a stable cheek support.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. The patient interface includes anasal seal to sealingly communicate with the patient's nose in use andheadgear to maintain the nasal seal in a desired position on thepatient's face. The headgear includes side straps each having arigidizer with a slotted connector portion and a rear or back straphaving ends that connect to a respective slotted connector portion.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. The patient interface includes aframe, a nasal prong assembly provided to the frame and adapted toprovide an effective seal or interface with the patient's nose, an elbowprovided to the frame and adapted to be connected to an air deliverytube that delivers breathable gas to the patient, and headgear adaptedto support the patient interface in a desired position on the patient'shead. The frame is relatively harder than the nasal prong assembly andrelatively softer and more flexible than the elbow. In an embodiment,the frame is relatively softer and more flexible than the elbow and/orheadgear yokes of the headgear. In an embodiment, the nasal prongassembly includes a gusset that allows a range of axial and lateralmovement while maintaining a sufficient seal. In an embodiment, theheadgear yoke of the headgear includes a yoke to frame interfacestructured to retain the headgear yoke to the frame, provide rotationrelative to the frame, and provide a friction element to providesufficient rotational torque (e.g., to reduce tube drag, to providetactile/audible feedback).

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. The patient interface includes aframe, a nasal prong assembly provided to the frame and adapted toprovide an effective seal or interface with the patient's nose, an elbowprovided to the frame and adapted to be connected to an air deliverytube that delivers breathable gas to the patient, and headgear adaptedto support the patient interface in a desired position on the patient'shead. The headgear includes side straps and rigidizers provided torespective side straps. Each rigidizer includes a frame interfacestructured to retain the rigidizer to the frame, provide rotationrelative to the frame, and provide a friction element to providesufficient rotational torque.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient. The patient interface includes apair of nasal prongs adapted to provide an effective seal or interfacewith the patient's nose and a support arrangement to support the nasalprongs in an operative position on the patient's face. The supportarrangement is structured to provide a range of rotational, axial, andlateral movement to the nasal prongs while maintaining a sufficient sealand resisting the application of tube drag and headgear tension to thenasal prongs.

Another aspect of the invention relates to a headgear link member forconnecting two or more straps of a headgear assembly for securing arespiratory mask to a patient. The link member is flexible and hasconnector portions for adjustable connection to said two or more straps.

Another aspect of the invention relates to a headgear assembly forsecuring a respiratory mask to a patient including a pair of rearheadgear straps located in use at a rear portion of the patient's headand a headgear link member connecting the rear headgear straps. Thestraps and link member are configured such that each strap passesthrough the link member in a single U-shape and is secured back toitself.

Another aspect of the invention relates to headgear for a patientinterface including a pair of side straps. Each of the side strapsincludes an upper strap portion adapted to pass over the top of thepatient's head, a front strap portion adapted to pass along the side ofthe patient's head, and a rear strap portion adapted to pass around arear portion of the patient's head. The free end of each rear strapportion includes a tab of hook material, and one side of each rear strapportion is coated with un-broken loop material which allows the tab ofhook material to fasten anywhere along its length.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient including a frame and a nasalprong assembly provided to the frame. The nasal prong assembly includesa pair of nasal prongs adapted to provide an effective seal or interfacewith the patient's nose. The nasal prong assembly includes a framecontacting portion that is adapted to be inserted and retained within aframe channel provided to the frame. The frame contacting portionincludes an external protrusion that is adapted to protrude through acorresponding opening provided in the frame channel.

Another aspect of the invention relates to a tube retainer for retainingan air delivery tube to a headgear strap of headgear. The tube retainerincludes a first strap portion adapted to loop around a headgear strapof headgear and a second strap portion provided to the first strapportion and adapted to loop around an air delivery tube. The first andsecond strap portions are integrally formed in one-piece from a soft andflexible material with the second strap portion extending transverse tothe first strap portion. Each strap portion includes a hook and looparrangement adapted to secure the respective strap portion in position.

Another aspect of the invention relates to a tube retaining assembly forretaining air delivery tubing including a headgear buckle includingopposing locking portions adapted to be removably and adjustably coupledwith respective headgear straps of headgear and a tube retainer providedto the headgear buckle. The tube retainer includes a pair of arcuatearms adapted to retain air delivery tubing.

Other aspects, features, and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1-1 is a perspective view of headgear for a patient interfaceaccording to an embodiment of the present invention;

FIGS. 2-1 and 2-2 are perspective views of a nasal prong assembly for apatient interface according to an embodiment of the present invention;

FIGS. 2-3 and 2-4 are top and front views of a nasal prong assembly fora patient interface and showing exemplary dimensions according to anembodiment of the present invention;

FIG. 3-1 is a perspective view of dual wall nasal prongs according to anembodiment of the present invention;

FIG. 4-1 is a schematic view of a trampoline-like suspension system fora nasal prong and showing exemplary dimensions according to anembodiment of the present invention;

FIG. 4-2 is a schematic view of a trampoline-like suspension system fora nasal prong according to another embodiment of the present invention;

FIGS. 5-1 to 5-40 illustrate nasal prongs and nasal prong assembliesaccording to alternative embodiments of the present invention;

FIG. 5-41 illustrates a nasal prong assembly and air delivery conduitaccording to another embodiment of the present invention;

FIG. 5-42-1 to 5-42-6 are various views of a tube retainer according toan embodiment of the present invention;

FIG. 5-43-1 to 5-43-7 are various views of a headgear buckle accordingto an embodiment of the present invention;

FIGS. 5-44-1 to 5-44-4 are respectively side, top, cross-section (alongline 5-44-3 of FIG. 5-44-2), and bottom orthogonal views of a linkaccording to an embodiment of the present invention;

FIG. 5-44-5 is an isometric view of the link shown in FIGS. 5-44-1 to5-44-4;

FIG. 5-45 is a cross-section showing the connection between the headgearstraps and the link shown in FIGS. 5-44-1 to 5-44-4;

FIG. 5-46 shows a portion of a prior art headgear buckle and strapassembly in use;

FIGS. 5-47-1 to 5-47-6 are various views of a tube retainer according toan embodiment of the present invention;

FIG. 5-48 is an isometric view of a buckle according to an embodiment ofthe present invention;

FIG. 5-49 is an isometric view of a buckle according to anotherembodiment of the present invention;

FIG. 5-50 is a side view of a buckle according to another embodiment ofthe present invention;

FIG. 5-51 is a side view of a buckle according to another embodiment ofthe present invention;

FIG. 5-52 is an isometric view of a buckle according to anotherembodiment of the present invention;

FIG. 5-53 is an isometric view of a buckle according to anotherembodiment of the present invention;

FIG. 5-54 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-55 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-56 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-57 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-58 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-59 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-60 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-61 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-62 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-63 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-64 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-65 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-66 is an isometric view of the keyhole of a buckle according toan embodiment of the present invention;

FIG. 5-67 is a top view of a buckle according to another embodiment ofthe present invention;

FIG. 5-68 is an isometric view of a tube retainer according to anembodiment of the present invention;

FIG. 5-69 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-70 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-71 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-72 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-73 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-74 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-75 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-76 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-77 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-78 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-79 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-80 is a front view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-81 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-82 is an isometric view of a tube retainer according to anotherembodiment of the present invention;

FIG. 5-83 is an isometric view of the tab of a tube retainer accordingto an embodiment of the present invention;

FIG. 5-84 is an isometric view of the tab of a tube retainer accordingto another embodiment of the present invention;

FIG. 5-85 is an isometric view of the tab of a tube retainer accordingto another embodiment of the present invention;

FIG. 5-86 is an isometric view of the tab of a tube retainer accordingto another embodiment of the present invention;

FIGS. 6-1 to 6-5 illustrate headgear yoke for headgear according to anembodiment of the present invention;

FIG. 7-1 schematically illustrates headgear tension on ResMed's MirageSwift headgear;

FIG. 7-2 schematically illustrates headgear tension on headgearaccording to an embodiment of the present invention;

FIGS. 8-1 to 8-4 schematically illustrate headgear yoke according toalternative embodiments of the present invention;

FIG. 9 illustrates a rear strap for headgear according to an embodimentof the present invention;

FIGS. 10-1 illustrates a headgear strap section including a headgearstrap and headgear yoke according to an embodiment of the presentinvention;

FIGS. 10-2-1 and 10-2-2 illustrate foam headgear straps according to anembodiment of the present invention;

FIG. 10-3-1 illustrates a cheek mark region with respect to ResMed'sSwift headgear;

FIG. 10-3-2 illustrates a known headgear strap section;

FIG. 10-4 illustrates a headgear strap section according to anembodiment of the present invention;

FIGS. 10-5 and 10-6 illustrate headgear straps and headgear yokesaccording to alternative embodiments of the present invention;

FIGS. 10-7-1 to 10-7-3 illustrate headgear including a friction padaccording to an embodiment of the present invention;

FIGS. 10-8-1 to 10-8-3 illustrate a nasal prong assembly including wingsaccording to an embodiment of the present invention;

FIGS. 10-9-1 to 10-9-3 illustrate headgear including foam paddingaccording to an embodiment of the present invention;

FIG. 10-9-4 illustrates headgear with yoke and wing without foam paddingaccording to another embodiment of the present invention;

FIGS. 11-1 and 11-2 illustrate cutting profiles for headgear strapsaccording to embodiments of the present invention;

FIGS. 12-1 to 12-26-2 illustrate headgear according to alternativeembodiments of the present invention;

FIGS. 13-1 to 13-4 illustrate various views of a patient interface on apatient's head according to an embodiment of the present invention;

FIG. 13-5 is a schematic view illustrating headgear vectors according toan embodiment of the present invention;

FIGS. 14-1 to 14-2 illustrate various views of the patient interfaceshown in FIGS. 13-1 to 13-4 with the headgear straps removed;

FIGS. 15-1 to 15-12 illustrate various views of the frame of the patientinterface shown in FIGS. 13-1 to 13-4;

FIGS. 16-1 to 16-12 illustrate various views of the nasal prong assemblyof the patient interface shown in FIGS. 13-1 to 13-4;

FIGS. 16-13-1 to 16-13-7 illustrate a nasal prong assembly according toan embodiment of the present invention;

FIG. 16-14-1 illustrates an assembled view of a nasal prong assembly andframe according to another embodiment of the present invention;

FIG. 16-14-2 illustrates an unassembled view of the nasal prong assemblyand frame shown in FIG. 16-14-1;

FIG. 16-14-3 is a perspective view of a patient interface including thenasal prong assembly and frame of FIG. 16-14-1;

FIGS. 16-15-1 to 16-15-10 illustrate various views of the nasal prongassembly of FIG. 16-14-1;

FIGS. 16-16-1 to 16-16-8 illustrate various views of the frame of FIG.16-14-1;

FIG. 16-17 is a perspective view of a nasal prong assembly and frameaccording to another embodiment of the present invention;

FIG. 16-18-1 is a perspective view of a nasal prong assembly and frameaccording to another embodiment of the present invention;

FIG. 16-18-2 illustrates an unassembled view of the nasal prong assemblyand frame shown in FIG. 16-18-1;

FIG. 16-18-3 illustrates a frame according to an embodiment of thepresent invention;

FIG. 16-19 is a perspective view of a nasal prong assembly and frameaccording to another embodiment of the present invention;

FIG. 16-20 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to an embodiment of thepresent invention;

FIG. 16-21 is a cross-sectional view of a frame according to anembodiment of the present invention;

FIG. 16-22 is a cross-sectional view of a frame according to anotherembodiment of the present invention;

FIG. 16-23 is a cross-sectional view of a frame according to anotherembodiment of the present invention;

FIG. 16-24 is a cross-sectional view of a frame according to anotherembodiment of the present invention;

FIG. 16-25 is a cross-sectional view of a frame contacting portion of anasal prong assembly according to an embodiment of the presentinvention;

FIG. 16-26 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to an embodiment of thepresent invention;

FIG. 16-27 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-28 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-29 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-30 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-31 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-32 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-33 is a cross-sectional view of a frame contacting portion of anasal prong assembly and a frame according to another embodiment of thepresent invention;

FIG. 16-34-1 is a cross-sectional view of a frame contacting portion ofa nasal prong assembly according to an embodiment of the presentinvention;

FIG. 16-34-2 is a cross-sectional view of a frame contacting portion ofa nasal prong assembly according to an embodiment of the presentinvention;

FIG. 16-35 is a rear view of a frame and frame channel according to anembodiment of the present invention;

FIG. 16-36 is a rear view of a frame and frame channel according toanother embodiment of the present invention;

FIG. 16-37 is a perspective view of a nasal prong assembly including aframe contacting portion according to an embodiment of the presentinvention;

FIG. 16-38 is a rear view of a frame and frame channel according toanother embodiment of the present invention;

FIG. 16-39 is a cross-sectional view of a frame contacting portion of anasal prong assembly according to another embodiment of the presentinvention;

FIG. 17 is a cross-sectional view of the patient interface shown inFIGS. 13-1 to 13-4;

FIGS. 18-1 to 18-7 illustrate various views of the elbow of the patientinterface shown in FIGS. 13-1 to 13-4;

FIGS. 18-8-1 to 18-8-9 illustrate various views of an elbow according toanother embodiment of the present invention;

FIG. 18-8-10 is a cross-sectional view through line 18-8-10-18-8-10 ofFIG. 18-8-5;

FIG. 18-8-11 is an enlarged portion of FIG. 18-8-10;

FIG. 18-8-12 is a cross-sectional view through line 18-8-12-18-8-12 ofFIG. 18-8-10;

FIG. 18-8-13 is an enlarged portion of FIG. 18-8-12;

FIG. 18-8-14 is a cross-sectional view similar to FIG. 18-8-10 inperspective;

FIG. 18-8-15 is an enlarged portion of FIG. 18-8-14;

FIG. 18-8-16 shows the elbow attached to the frame and nasal prongassembly according to an embodiment of the present invention;

FIG. 18-8-17 shows the interface between the elbow and the short tubeaccording to an embodiment of the present invention;

FIGS. 18-9-1 to 18-9-3 are various views of an elbow to frame attachmentaccording to an embodiment of the present invention;

FIGS. 18-10-1 to 18-10-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-11-1 to 18-11-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-12-1 to 18-12-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-13-1 to 18-13-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-14-1 to 18-14-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-15-1 to 18-15-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-16-1 to 18-16-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-17-1 to 18-17-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 18-18-1 to 18-18-3 are various views of an elbow to frameattachment according to another embodiment of the present invention;

FIGS. 19-1 to 19-5 illustrate various views of headgear yoke of thepatient interface shown in FIGS. 13-1 to 13-4;

FIGS. 19-6 and 19-7 are enlarged views of the yoke to frame interface ofthe headgear yoke shown in FIGS. 19-1 to 19-5;

FIG. 19-8 is a cross-sectional view illustrating the yoke to frameinterface attached to a respective frame connector according to anembodiment of the present invention;

FIGS. 19-9-1 to 19-9-6 are sequential views illustrating attachment ofthe yoke to frame interface to a respective frame connector according toan embodiment of the present invention;

FIGS. 19-10 to 19-13 illustrate exemplary dimensions of the headgearyoke according to an embodiment of the present invention;

FIG. 19-14 is a side view illustrating rotational movement of thepatient interface according to an embodiment of the present invention;

FIGS. 19-15-1 to 19-15-5 are sequential views illustrating rotationaladjustment of the headgear yoke with respect to the frame according toan embodiment of the present invention;

FIG. 19-16 is a top view of the patient interface on a patient's headaccording to an embodiment of the present invention;

FIG. 19-17-1 to 19-17-4 illustrate various cross-sections through theheadgear yoke according to an embodiment of the present invention;

FIG. 19-18 is a perspective view of the patient interface showingexemplary dimensions according to an embodiment of the presentinvention;

FIG. 19-19 is a cross-sectional view of the headgear yoke showingexemplary dimensions according to an embodiment of the presentinvention;

FIG. 19-20 is a cross-sectional view illustrating headgear yoke attachedto a headgear strap according to an embodiment of the present invention;

FIGS. 19-21-1 to 19-21-3 illustrate a yoke to frame rotation indicatoraccording to an embodiment of the present invention;

FIGS. 19-22-1 to 19-22-4 illustrate a yoke to frame rotation indicatoraccording to another embodiment of the present invention;

FIGS. 19-23-1 to 19-23-4 illustrate a yoke to frame rotation indicatoraccording to another embodiment of the present invention;

FIG. 20-1 is a perspective view of a short tube according to anembodiment of the present invention;

FIGS. 20-2 to 20-4 are various views illustrating attachment of theshort tube to a swivel according to an embodiment of the presentinvention;

FIGS. 20-5-1 to 20-5-6 illustrate a short tube with elbow and swivelaccording to another embodiment of the present invention;

FIGS. 21-1 and 21-2 illustrate Velcro tabs for a headgear strapaccording to embodiments of the present invention;

FIGS. 22-1-1 to 22-1-8 are various views of a frame according to anembodiment of the present invention;

FIGS. 22-1-9 and 22-1-10 illustrate rotation of the yoke relative to theframe according to an embodiment of the present invention;

FIGS. 22-2 and 22-3 illustrate assembly of headgear yoke to a frameaccording to an embodiment of the present invention;

FIGS. 22-4 to 22-6 and 22-7-1 to 22-7-8 are various views of a headgearyoke according to an embodiment of the present invention;

FIGS. 22-8 to 22-13 are various views illustrate attachment of headgearyoke to a frame according to an embodiment of the present invention;

FIGS. 22-14 and 22-15 illustrate a ratchet arrangement between headgearyoke and frame according to an embodiment of the present invention;

FIG. 22-16 illustrates a fully assembled frame and headgear yokeaccording to an embodiment of the present invention;

FIGS. 22-16-1 and 22-16-2 illustrate an interference fit between theyoke and the frame according to an embodiment of the present invention;

FIGS. 22-17-1 to 22-17-2 illustrate relative movement between the frameand headgear yoke according to an embodiment of the present invention;

FIGS. 22-18-1 to 22-18-3 illustrate a mold for molding a frame accordingto an embodiment of the present invention;

FIGS. 22-19-1 to 22-19-7 illustrate headgear yoke attached to a headgearstrap according to an embodiment of the present invention;

FIGS. 22-20-1 to 22-20-5 illustrate a fully assembled patient interfaceaccording to an embodiment of the present invention;

FIGS. 22-20-6 and 22-20-7 illustrate a back strap for a patientinterface according to an embodiment of the present invention;

FIGS. 22-21-1 to 22-21-8 illustrate a left-hand-side (LHS) side strapwith headgear yoke according to an embodiment of the present invention;

FIGS. 22-22-1 to 22-22-8 illustrate a right-hand-side (RHS) side strapwith headgear yoke according to an embodiment of the present invention;

FIGS. 22-22-9 and 22-22-10 illustrate under-side and top-side views of atab of hook material according to an embodiment of the presentinvention;

FIGS. 22-23-1 to 22-23-7 illustrate a fully assembled patient interfaceaccording to an embodiment of the present invention;

FIG. 22-24 is a perspective view showing a yoke engaged with a frame viaa ball and socket joint according to an embodiment of the presentinvention;

FIG. 22-25 is a cross-sectional view showing the ball and socket jointof FIG. 22-24;

FIG. 23 illustrates the difference in compression before bottoming outbetween prior art nasal pillow mask systems (Puritan-Bennett Breeze),related art nasal pillow system (ResMed Swift II) and an embodiment ofthe present invention;

FIG. 24 illustrates the difference in lateral movement that can beobtained in accordance with an embodiment of the present invention whencompared to ResMed Swift nasal pillows;

FIG. 25a to FIG. 25g show cross-sectional profiles of a range of priorand related nasal pillow systems, as well as an embodiment of thepresent invention;

FIG. 26 shows a table comparing relative properties of the ResMed SWIFTmask and an embodiment of the present invention;

FIG. 27a to FIG. 27l show a range of views of a nasal pillow and gussetassembly in accordance with another embodiment of the present invention,FIG. 27 is similar to FIG. 16;

FIG. 28 is a sketch illustrating how the nasal pillows and gusset alignwith the face in use;

FIG. 29 is a sketch comparing a nasal pillow of an embodiment of thepresent invention and a prior art nasal pillow when subject to acompression force;

FIG. 30 is a cross-section of headgear material according to anembodiment of the present invention;

FIGS. 31-1 and 31-2 are perspective views of a mask system according toanother embodiment of the present invention;

FIGS. 32-1 and 32-2 are perspective views of a mask system according toanother embodiment of the present invention;

FIGS. 33-1 and 33-2 are side and front views of a mask system accordingto another embodiment of the present invention;

FIG. 34 is a perspective view of a mask system according to anotherembodiment of the present invention;

FIG. 35 is an exploded view of a mask system according to anotherembodiment of the present invention;

FIG. 36 is a perspective view of a mask system according to anotherembodiment of the present invention;

FIG. 37 is a perspective view of a mask system according to anotherembodiment of the present invention;

FIG. 38 is a perspective view of a mask system according to anotherembodiment of the present invention;

FIGS. 39-1 and 39-2 are perspective views of a mask system according toanother embodiment of the present invention;

FIG. 40 is a cross-sectional view of a mask system according to anotherembodiment of the present invention;

FIG. 41-1 illustrates a nasal prong assembly having a width and FIG.41-2 illustrates a nasal prong assembly having a smaller width accordingto an embodiment of the present invention;

FIG. 41-3 is a cross-sectional view of the nasal prong assembly shown inFIG. 41-2;

FIG. 42 is a cross-sectional view of a mask system according to anotherembodiment of the present invention;

FIG. 43 is a cross-sectional view of a mask system according to anotherembodiment of the present invention;

FIG. 44 is a cross-sectional view of a mask system according to anotherembodiment of the present invention; and

FIG. 45-1 illustrates a nasal prong assembly having a central axis andFIG. 45-2 illustrates a nasal prong assembly having a shifted centralaxis according to an embodiment of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

In broad terms, a patient interface in accordance with an embodiment ofthe invention may comprise three functional aspects: (i) interfacing,(ii) a positioning and stabilizing, and (iii) air delivery. These threefunctional aspects may be constructed from one or more structuralcomponents, with a given structural component potentially fulfillingmore than one function. For example, a mask frame may serve as part of apositioning and stabilizing function and allow the supply of air.

In addition, a patient interface in accordance with an embodiment of theinvention may perform other functions including venting of exhaledgases, decoupling of potentially seal disruptive forces and adjustmentfor different sized faces. Venting may be performed by differentstructures, such as a frame, an elbow and/or a conduit.

The following description is provided in relation to several embodimentswhich may share common characteristics and features. It is to beunderstood that one or more features of any one embodiment may becombinable with one or more features of the other embodiments. Inaddition, any single feature or combination of features in any of theembodiments may constitute additional embodiments.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

The term “air” will be taken to include breathable gases, for exampleair with supplemental oxygen. It is also acknowledged that the positiveairway pressure (PAP) devices or flow generators described herein may bedesigned to pump fluids other than air.

Each illustrated embodiment includes features that may be used with theembodiments and/or components described in U.S. Patent ApplicationPublication Nos. 2004-0226566, 2006-0137690, and 2005-0241644, PCTApplication Publication Nos. WO 2005/063328, WO 2006/130903, and WO2007/053878, and U.S. Provisional Application Nos. 60/835,442, filedAug. 4, 2006, and 60/852,649, filed Oct. 19, 2006, as would be apparentto those of ordinary skill in the art. Each of the above notedapplications are incorporated herein by reference in its entirety.However, it should be appreciated that any single feature or combinationof features in any of the embodiments may be applied to other suitablemask arrangements, e.g., full-face, etc.

1 Interfacing

1.1 Introduction

In one form of the invention, the interfacing function is provided by apair of nasal prongs (or “nasal pillows”) that are placed at an entranceto the patient's nares. Each prong is structured to form an adequateseal with its respective naris and is shaped, oriented, sized andconstructed so as provide a fit with a range of differently shaped andlocated nares.

As shown in FIGS. 2-1 to 2-2, the nasal prong assembly 20 includes abase 22 and a pair of nasal prongs 24 provided to the base 22. Eachnasal prong 24 includes a generally conical, “volcano”, ormushroom-shaped head portion 25 adapted to seal and/or sealinglycommunicate with a respective patient nasal passage (e.g., concave andoval prong designed to fit into the patients nares and seal against therim of the nares) and a column or stalk 27 that interconnects the headportion 25 with the base 22. The nasal prong assembly 20 is structuredto be removably and replaceably attached to a substantially rigid frame30 and be retained to the frame 30 by a clip 23 (such as that describedin WO 2007/053878, which is incorporated herein by reference in itsentirety). One or more vent openings 32 may be provided in the frameand/or base for CO₂ washout.

The nasal prong assembly 20 may be integrally formed in one-piece, e.g.,by silicone in an injection molding process (e.g., LSR (liquid siliconerubber) and CMSR (compression molded silicon rubber) moldingtechnology). However, the nasal prong assembly 20 may be formed in othersuitable processes.

In an embodiment, one end of the nasal prong assembly is provided with aplug and the other end is provided with an elbow (e.g., swivel elbow).The positions of the elbow and the plug may be interchanged, accordingto preference, e.g., the typical sleeping position of the patient. In analternative embodiment, both ends of the nasal prong assembly may beprovided with an elbow. An air delivery tube is joined to the elbow orelbows to deliver a source of pressurized gas (e.g., 2-30 cmH2O).

In an embodiment, the nasal prong assembly may include a “low flow”version with a different pressure flow requirement.

The nasal prong assembly provides a lightweight, unobtrusive arrangementfor delivering positive airway pressure as a means of therapy, e.g., forOSA.

The following discussion in the “Interfacing” section of this detaileddescription principally relates to the cone-shaped portion of the prong,other aspects of the prong—such as the stalk—will be discussed in moredetail in subsequent sections.

1.2 Shape, Geometry and Anthropometrical Features

The nasal prongs may include geometry and/or anthropometrical featuressimilar to the nasal prongs described in U.S. Patent ApplicationPublication Nos. 2004-0226566, 2006-0137690 and PCT ApplicationPublication Nos. WO 2006/130903, and WO 2007/053878, each of which isincorporated herein by reference in its entirety.

Also, rotating the nasal prong assembly in relation to the headgear canphysically rotate the prongs in an anterior/posterior direction inrelation to the nose. This flexibility effectively sets the prongs intoan “exact” comfortable position for an individual user.

Further, the prong's stalk provides a flexible point to allow prongalignment and seal maintenance.

1.3 Orientation

For example, the orientation of the nasal prongs is designed to presentthe exit holes and the conical sealing surfaces as square to the nostrilopenings as possible. This increases the effectiveness of the seal. Theprongs have been angled and rotated in relation to the base in order toprovide this orientation for average anthropometry.

As shown in top view FIG. 2-3 (nostril angle), the rotation angle α ofthe prong 24 with respect to centerline CL may about 20-35 degrees,e.g., 27 degrees. As shown in front view FIG. 2-4 (alar angle), theinward rotation angle β of the prong 24 with respect to centerline CLmay be about 15-20 degrees, e.g., 17 degrees. However, other suitableangles are possible.

1.4 Sizing

In combination with this orienting geometry, the prongs can be adaptedto nasal geometry variations from patient to patient in a number ofways. Firstly, the prongs may be available in multiple sizes (e.g.,extra small, small, medium, large, extra large). The variant geometrybetween sizes may be the diameters of the oval prong profile.

1.5 Spacing

Spacing of the pillows is illustrated in FIG. 16-8 described below.

1.6 Construction

1.6.1 Dual-Wall Nasal Prongs

In an embodiment, the nasal prongs 24 may be similar to nasal prongsthose described in WO 2006/130903, which is incorporated herein byreference in its entirety.

For example, as shown in FIG. 3-1, the head portion 25 of each nasalprong 24 may include a dual or double-wall arrangement including aninner wall 26 (inner membrane or support membrane) and an outer wall 28(outer membrane or sealing membrane) that surrounds the inner wall 26.The outer wall 28 may be relatively thin (e.g., 0.35 mm) to conform tothe shape of the patient's nose and provide a more compliant seal. Inaddition, the thin outer wall effectively finds its own seal with verylittle tweaking, which reduces the time for set-up. In an embodiment,the dual-wall prongs 24 may be manufactured in a manner as described inWO 2006/130903, e.g., fold or invert one wall with respect to the otherwall.

One of the advantages of dual wall nasal prongs that may be used toimprove jetting performance is that it is possible to reorient the innerexit hole at any angle while retaining a “square” sealing orientationfor the outer wall.

One aspect of dual pillows construction is that the inner surface of theouter membrane may be frosted to facilitate removal from the moldingtool. Also, the outer surface of the outer membrane may be frosted,e.g., for comfort and for improving fitting to nose because lesssticking.

1.6.2 Alternative Nasal Prong Embodiments

The following embodiments describe alternative prong arrangements thatare structured to improve sealing comfort and/or fitting. Inembodiments, the prong arrangements may be structured to reduce and/oreliminate the air jetting effect, e.g., redirect air flow direction(e.g., away from sensitive regions such as the septum), diffuse air flowor create turbulence, and/or change the prong orifice in order to reduceand/or eliminate air jetting effects. Reducing and/or eliminating theair jetting effect may provide increased comfort across a wider pressurerange and/or reduced concentrated dryness and cold burning sensation. Inaddition, adding turbulence may reduce noise.

Additional prong arrangements to improve comfort and fitting aredescribed in U.S. Provisional Application Nos. 60/835,442, filed Aug. 4,2006, and 60/852,649, filed Oct. 19, 2006, each of which is incorporatedherein by reference in its entirety.

The nasal prong embodiments described below include a dual ordouble-wall head portion. While embodiments described below relate todual-wall nasal prongs, it should be appreciated that embodiments of theinvention may be adapted for use with single-wall nasal prongs and/ormulti-wall nasal prongs (e.g., 2 or more walls).

Dual Wall with Hood

FIG. 5-1 illustrates a nasal prong 224 according to another embodimentof the present invention. In the illustrated embodiment, the inner wall226 includes a hood 234 (e.g., integrally formed with the inner wall)adapted to reorient the exit hole and change the air flow direction toreduce and/or eliminate the air jetting effect, e.g., direct flow awayfrom the septum.

As illustrated, the hood 234 is provided to anterior and medial portions(i.e., front and middle portions) of the inner wall 226 along theperimeter of the orifice. The hood 234 is structured to direct the airposteriorly, e.g., towards the rear, rather than straight up the nasalpassage. In addition, the hood 234 is structured to direct the airlaterally, e.g., towards the side, rather than towards the septum. Thus,the hood 234 is structured to change the air flow in two planes suchthat the hood 234 directs the air flow away from the septum and avoidsdirect contact with sensitive areas of the anterior nose.

Dual Wall with Dome

FIG. 5-2 illustrates a nasal prong 324 according to another embodimentof the present invention. In the illustrated embodiment, the inner wall326 includes a dome 335 (e.g., integrally formed with the inner wall)adapted to change the air flow direction to reduce and/or eliminate theair jetting effect, e.g., direct flow away from the septum. The dome 335may also reduce pressure drop and/or impedance.

As illustrated, the dome 335 has a hemispherical shape that extends overthe orifice of the inner wall 326 and provides an eccentrically placedexit hole to direct the air away from sensitive regions of the patient'snose, e.g., septum. In an embodiment, the exit hole may be positioned todirect air similar to the hood described above, e.g., direct the airposteriorly and laterally.

Dual Wall with Blocked Orifice and Holes on Inner and Outer Walls

FIG. 5-3 illustrates a nasal prong 424 according to another embodimentof the present invention. In the illustrated embodiment, the orifice ofthe inner wall 426 is blocked and the inner wall 426 includes one ormore holes 436. As illustrated, the holes 436 are provided to aposterior side of the inner wall 426. However, the holes 436 may beprovided along any suitable portion of the inner wall 426. Also, eachhole 436 has a generally circular or oval shape. In alternativeembodiments, each hole 436 may have any other suitable shapes, e.g.,non-circular such as elongated slots or square or rectangular openings.In addition, the inner wall 426 may have any suitable number of holes436, e.g., 1, 2, 3, or more holes.

Further, the outer wall 428 may optionally include one or more holes437. In the illustrated embodiment, the holes 437 are provided to anupper region of the outer wall (e.g., near the orifice) on a medialportion of the outer wall which is oriented towards the patient's facein use (e.g., near the patient's top lip). Similar to the holes 436 inthe inner wall, the holes 437 in the outer wall may be provided to othersuitable portions of the outer wall, may be have other suitable shapes,and may have any suitable number of holes, e.g., 1, 2, 3, or more holes.

In the illustrated embodiment, the holes 436 in the inner wall arelarger than the holes 437 in the outer wall. However, other suitablesizes are possible.

In use, the holes 436, 437 disperse air as it passes through the prong424, e.g., to create turbulence and/or reduce impedance.

Dual Wall with Blocked Orifice and Castellated Openings

FIG. 5-4 illustrates a nasal prong 524 according to another embodimentof the present invention. In the illustrated embodiment, the orifice ofthe inner wall 526 is blocked and the inner wall 526 includes one ormore openings 536 around the perimeter or rim of the inner wall 526adjacent the blocked orifice. As illustrated, the openings 536 eachinclude a generally square or rectangular shape to provide acastellated-type arrangement at the top of the inner wall 526. However,the openings 526 may have other suitable shapes and may be provided inany suitable number, e.g., 5, 6, 7, or more openings.

In use, the openings 536 direct the flow laterally from the blockedorifice to disperse and/or diffuse air as it passes through the prong,e.g., to create turbulence.

In an alternative embodiment, the orifice of the inner wall 526 may notbe blocked and the top of the inner wall 526 may include thecastellated-type arrangement to disperse air.

Dual Wall with Elongated Inner Wall

FIG. 5-5 illustrates a nasal prong 624 according to another embodimentof the present invention. In the illustrated embodiment, the inner wall626 is elongated or extended so that the orifice of the inner wall 626is substantially higher than the orifice of the outer wall 628. Inaddition, the inner wall 626 has a tube-like configuration with theorifice of the inner wall 626 oriented to change the air flow directionto reduce and/or eliminate the air jetting effect, e.g., direct flowaway from the septum. In an embodiment, the orifice may be oriented todirect air similar to the hood described above, e.g., direct the airposteriorly and laterally. For example, the inner wall 626 extendsfurther inside the patient's nostril to direct flow away from the innerseptum.

Dual Wall with Insert

FIG. 5-6 illustrates a nasal prong 724 according to another embodimentof the present invention. In the illustrated embodiment, an insert 738(i.e., formed separately from the prong) is provided to the inner wall726 that is adapted to change the air flow direction to reduce and/oreliminate the air jetting effect, e.g., direct flow away from theseptum.

As illustrated, the insert 738 includes a base 738(1) adapted to supportthe insert 738 in a operative position adjacent the orifice of the innerwall 726 and a head 738(2) that provides an exit opening to change theair flow direction. The length of the head 738(2) may be changed, e.g.,customized length for particular patient, to provide a longer or shorterexit from the inner wall 726. In the illustrated embodiment, the wall ofthe insert 738 may be constructed of a foam or silicone material.Alternatively, the entire volume of the insert 738 may be constructed offoam, e.g., similar to the foam insert described below.

The insert 738 is secured to the inner wall 726 to prevent removal andpossible inhalation in use. In an embodiment, the inner wall 726 mayinclude an annular flange or shoulder around the orifice adapted tosupport or secure the insert 738 in position. However, the insert 738may be supported in its operative position in other suitable manners,e.g., adhesive, friction fit, mechanical interlock, etc. In anembodiment, a connector may be provided between inserts of adjacentprongs to prevent discharge of an insert through the orifice, e.g.,during inspiration.

In an embodiment, the insert 738 may be retrofitted to an existing nasalprong in order to direct flow in a similar manner to a hood. Forexample, the exit opening of the insert 738 may be positioned to directair in a similar manner to the hood described above, e.g., direct theair posteriorly and laterally. Thus, the insert 738 may be made as a“spare part” or separate accessory and used only when the patient issuffering from jetting effect with an existing nasal prong assembly.

Dual Wall with Internal Ledge

FIG. 5-7-1 illustrates a nasal prong 824 according to another embodimentof the present invention. In the illustrated embodiment, the prong 824includes an internal ledge or shelf 839 that extends inwardly from theinner wall 826 to block at least a portion of the flow exiting theorifice of the inner wall 826. In an embodiment, the ledge or shelf 839is positioned on a medial portion of the inner wall 826 so that theledge or shelf 839 is adapted to block flow nearest to the patient'sseptum in use. However, the ledge or shelf 839 may be provided at otherportions of the inner wall 826 to block air flow directed at sensitiveregions.

As illustrated, the ledge or shelf 839 extends inwardly from the edge ofthe orifice. In an alternative embodiment, the ledge or shelf 839 may bespaced downwardly from the edge of the orifice, e.g., to reduceimpedance.

In yet another alternative, as shown in FIG. 5-7-2, a ledge or shelf 839may be provided to a single wall prong. For example, the ledge or shelf839 may extend inwardly from the wall of the prong to block at least aportion of the flow exiting the orifice, e.g., block flow nearest to thepatient's septum.

Dual Wall with Mesh or Gauze

FIG. 5-8 illustrates a nasal prong 924 according to another embodimentof the present invention. In the illustrated embodiment, the prong 924includes mesh or gauze 940 constructed of a suitable mesh or gauzematerial (e.g., auxetic materials possible) to diffuse the flow of air.As illustrated, the mesh or gauze 940 is provided at the base of thehead portion. However, the mesh or gauze 940 may be provided at othersuitable locations along the prong, e.g., at the base of the stalk. Inan embodiment, the mesh or gauze 940 may be provided as an insert thatis retrofit to an existing nasal prong.

In use, the mesh or gauze 940 increases the dispersion and turbulence ofthe air as it exits the prong orifice and enters the patient's nasalpassage.

In an alternative embodiment, the mesh or gauze 940 may be designed asan anti-asphyxia valve (AAV) style flap adapted to cover the prongorifice on inspiration and fall open on expiration to reduce impedance.

Dual Wall with Exit Gate

FIG. 5-9-1 illustrates a nasal prong 1024 according to anotherembodiment of the present invention. In the illustrated embodiment, theprong 1024 includes a pinwheel-shaped or star-shaped gate 1041, e.g.,integrally formed with the prong, provided at the rim or exit orifice ofthe inner wall 1026. As illustrated, the pinwheel-shaped or star-shapedgate 1041 includes a hub 1041(1) and a plurality of vanes or legs1041(2) extending radially from the hub 1041(1). Each vane 1041(2)tapers from the rim to the hub.

In use, the gate 1041 increases the dispersion and turbulence of the airas it exits the orifice and enters the patient's nasal passage.

It should be appreciated that the gate 1041 may be provided at othersuitable locations along the prong (e.g., at the outer wall, along thestalk, etc.), and the gate 1041 may have other suitable shapes andorientations. In addition, the gate 1041 may have any suitable number ofvanes 1041(2), e.g., 3, 4, 5, or more vanes.

For example, FIG. 5-9-2 illustrates a prong 1124 with a gate 1141according to another embodiment of the present invention. Asillustrated, the gate 1141 includes a hub 1141(1) and a plurality ofvanes 1141(2) extending radially from the hub 1141(1). Each vane 1141(2)is helical or in the shape of a propeller blade to disperse the air andcreate turbulence as it exits the orifice.

In yet another alternative, such a pinwheel-shaped or star-shaped gatemay be provided to a single wall prong, e.g., at the exit orifice of theprong.

Dual Wall with Foam Insert

FIG. 5-10 illustrates a nasal prong 1224 according to another embodimentof the present invention. In the illustrated embodiment, the prong 1224includes a foam insert 1238 constructed of a foam material, e.g., lowdensity foam material, to diffuse the flow of air. As illustrated, thefoam insert 1238 is provided within the cavity defined by the inner wall1226. However, the foam insert 1238 may be provided at other suitablelocations along the prong, e.g., within the stalk. In an embodiment, thefoam insert 1238 may be provided as a “spare part” that is adapted to beretrofitted to an existing nasal prong.

The foam insert 1238 may be supported by the inner wall 1226 in itsoperative position in any suitable manner, e.g., adhesive, friction fit,mechanical interlock, etc. For example, the foam insert 1238 may besqueezed into the cavity and then allowed to resiliently expand intoengagement with the inner wall 1226. In an embodiment, a connector maybe provided between foam inserts of adjacent prongs to prevent dischargeof an insert through the orifice, e.g., during inspiration.

In use, air passes through the thickness of the foam insert 1238 whichincreases the dispersion and turbulence of the air as it exits the prongorifice and enters the patient's nasal passage.

In another alternative embodiment, each prong may include an insertconstructed of a silicone material and provided with relatively smallchannels through the interior to diffuse the flow of air in use. Insertsconstructed of other suitable materials are also possible, e.g.,Gore-Tex.

In yet another embodiment, the insert (e.g., foam or silicone insert)may provide a mechanical valve type arrangement. For example, the insertmay be adapted to cover the orifice and act as a diffuser oninspiration, and open or uncover the orifice on expiration. In anembodiment, the insert may include a cone-shape with a hollow center tofacilitate movement between covering and uncovering positions.

Dual Wall with Cut Inner Wall

FIG. 5-11 illustrates a nasal prong 1324 according to another embodimentof the present invention. In the illustrated embodiment, the orifice ofthe inner wall 1326 and/or the orifice of the outer wall 1328 is cut atan angle, e.g., 45° angle, to direct air flow. The angled orifice(s)changes the air flow direction to reduce and/or eliminate the airjetting effect, e.g., direct flow away from the septum. In addition, theangled orifice(s) increase the size of the orifice(s) (e.g., withrespect to a non-cut or non-angled orifice) to provide lower impedance.The prong orifice(s) may be cut at any suitable angle, e.g., angle maybe dependent on the shape of the patient's nostrils.

Dual Wall with Chevron-Pattern Exit Hole

FIGS. 5-12-1 and 5-12-2 illustrate nasal prongs 1424 according toanother embodiment of the present invention. In the illustratedembodiment, the orifice of the inner wall 1426 and/or the orifice of theouter wall 1428 includes a chevron-pattern or toothed arrangement aroundits perimeter. In FIG. 5-12-1, the prong includes a chevron-patternaround the orifice of the inner wall, 1426. In FIG. 5-12-2, the prongincludes a chevron-pattern around the orifice of the inner and outerwalls 1426, 1428.

However, the orifice may have other suitable shapes or patterns aroundits perimeter. For example, FIGS. 5-12-3 and 5-12-4 are tope top viewsof prongs including orifices with a series of contours or lobes 1442,e.g., 3, 4, 5, 6, or more contours or lobes.

In use, the non-oval-shaped orifice increases the dispersion andturbulence of the air as it exits the orifice and enters the patient'snasal passage.

Dual Wall with Alternative Base

FIGS. 5-13-1 and 5-13-2 illustrate a nasal prong 1524 and base 1522according to alternative embodiments of the present invention. In theillustrated embodiment, the base 1522 that supports the prong 1524 mayinclude different thicknesses to vary a trampoline or bounce effectprovided by the base 1522. For example, FIG. 5-13-1 illustrates a base1522 wherein d1 is about 0.6 mm and d2 is about 0.75-0.85 mm, and FIG.5-13-2 illustrates a base 1522 wherein d1 is about 0.85 mm and d2 isabout 0.75 mm. In each embodiment, the stalk 1527 may have a length d3of about 5.2 mm and a thickness d4 of about 0.6-1.0 mm. Also, in eachembodiment, the outer wall 1528 may have a thickness d5 of about 0.1 to0.5 mm, or about 0.35±0.1 mm, or about 0.3±0.1 mm, or about 0.45 mm. Therelatively thin outer wall 1528 may be more comfortable and compliant.The inner wall 1526 may have a thickness d6 of about 0.4 to 1.0 mm.

It is to be understood that these dimensions and ranges are merelyexemplary and other dimensions and ranges are possible depending onapplication. Also, such base may be provided to a nasal prong having asingle wall configuration.

Manufacturing

In an embodiment, the dual-wall prong may be molded into its operativedual wall construction. In an alternative embodiment, one of the innerand outer walls may be molded in an open position and then inverted orfolded to form the dual wall construction.

In yet another embodiment, as shown in FIG. 5-13-3, a prong 4424 mayinclude a multi-wall construction (e.g., triple-wall construction) inwhich two or more walls 4426(1), 4426(2) are molded in an open positionand then inverted or folded with respect to another wall 4426(3) to formthe multi wall construction (e.g., three wall concentric arrangement).Exemplary folded wall arrangements are described in WO 2006/130903,which is incorporated herein by reference in its entirety.

Thin Wall Thickness

FIG. 5-14-1 illustrates a nasal prong 1624 according to anotherembodiment of the present invention. In the illustrated embodiment, theoutermost wall 1628 (e.g., the outer wall of a multi-wall prong or thesingle wall of a single wall prong has a relatively thin wall thickness(e.g., thickness less than about 0.45 mm (e.g., 0.35 mm)) so that theoutermost wall is adapted to bulge outwardly or slightly inflate (asindicated in dashed lines in FIG. 5-14-1) in use to accommodate and/orconform to the patient's nose in use.

For example, FIG. 5-14-2 is a plan view of the outermost wall 1628 toillustrate its generally oval or elliptical shape, and FIGS. 5-14-3 and5-14-4 are cross-sectional views through minor and major axes of theoutermost wall respectively. As illustrated, the sides of the wall arestructured to bulge more outwardly than the ends of the wall in use.Specifically, the sides of the wall are adapted to move from a generallyconcave shape to a generally convex shape in use (see FIG. 5-14-3), andthe ends are adapted to move from a generally concave shape to agenerally straight or linear shape in use (see FIG. 5-14-4). Sucharrangement facilitates sealing and compliance of the prong with thepatient's nose in use as the thin wall is able to conform to thepatient's nasal contours.

Support of Thin Outer Wall

A support structure may be provided to a thin outer wall (such as thatdescribed above in FIGS. 5-14-1 to 5-14-4) to add rigidity and/orfacilitate alignment and engagement of the thin outer wall with thepatient's nose before use. In addition, the support structure may beconstructed and arranged to create turbulence in use.

For example, as shown in FIGS. 5-15-1 and 5-15-2, the thin outer wall1728 may include one or more ribs 1743 that extend along an interiorsurface of the outer wall, e.g., integrally formed with the thin outerwall.

In another embodiment, as shown in FIG. 5-16, the thin outer wall 1828may include a plurality of ribs 1843 that form concentric ribs or ringsalong an interior surface of the outer wall 1828, e.g., integrallyformed with the outer wall. The ribs 1843 may extend around the entireinterior perimeter of the outer wall and/or the ribs 1843 may extendaround portions of the interior perimeter of the outer wall.

In another embodiment, as shown in FIG. 5-17, the outer wall 1928 mayinclude a thin region 1928(1) positioned between a thicker rim 1928(2)along the orifice and a thicker base 1928(3).

In another embodiment, as shown in FIG. 5-18, the outer wall 2028 mayinclude a plurality of notches 2044 that form thinned sections 2028(1)along the outer wall 2028. The thinned sections 2028(1) may extendaround the entire interior perimeter of the outer wall and/or thethinned sections 2028(1) may extend around portions of the interiorperimeter of the outer wall.

In another embodiment, a dual wall prong may be provided and the innerwall may be substantially rigid (e.g., thickness greater than about 0.4mm (e.g., 0.4 to 0.8 mm)) in order to support and guide the thin outerwall into engagement with the patient's nose before use. That is, thethin outer wall provides a seal-forming thinner wall and the inner wallprovides a structure-defining thicker wall that adds stiffness to thethin outer wall as it is engaged and aligned with the patient's nosebefore use. In use, pressurized air causes the outer wall to bulgeoutwardly into conformance with the patient's nose, e.g., pressuresupported seal.

In another embodiment, as shown in FIGS. 5-19-1 to 5-19-3, a support rod2145 may be operatively engaged with the outer wall 2128 of the prong inorder to support and guide the outer wall 2128 thereof into engagementwith the patient's nose before use. As shown in FIG. 5-19-3, each prongincludes a pinwheel-shaped or star-shaped gate 2141 provided at the rimof the outer wall 2128. The support rod 2145 includes a first end2145(1) engaged with the hub of the gate 2141 and a second end 2145(2)that extends through the base 2122 supporting the prongs. In use, thepatient can slidably move the support rod 2145 via the exposed first end2145(2) in order to hold the outer wall in a sufficiently taut orextended position for engagement with the patient's nose before use (seeFIG. 5-19-2).

In another embodiment, as shown in FIGS. 5-20-1 to 5-20-2, supportprojections 2246 may be provided to the base 2222 supporting the prongsthat is adapted to operatively engage with the outer wall 2228 of arespective prong in order to support and guide the outer wall thereofinto engagement with the patient's nose before use. As illustrated, eachsupport projection 2246 is provided to the lower wall of the base 2222in alignment with a respective prong and includes a generally cone-likeshape. In use, the patient can deflect or deform the base 2222 so thateach support projection 2246 moves from an initial position (FIG.5-20-1) into an engaged position (FIG. 5-20-2) with the outer wall 2228of a respective prong. In the engaged position of FIG. 5-20-2, thesupport projection 2246 supports or holds the outer wall 2228 in asufficiently taut or extended position for engagement with the patient'snose before use.

1.6.3 Ball-Type Insert

FIG. 5-21 illustrates a nasal prong assembly 2320 according to anotherembodiment of the present invention. In the illustrated embodiment, aball-type insert 2338 (e.g., silicone or plastic ball) is provided tothe interior of each prong 2324. The ball-type insert 2338 has adiameter that is sufficiently larger than the diameter of the prongorifice to prevent discharge of the ball-type insert 2338 through theorifice, e.g., during inspiration. In use, the ball-type insert 2338moves or rotates freely within the prong interior to introduce variabledirection air flow, e.g., random diffuse of air, to reduce and/oreliminate the air jetting effect, e.g., reduce air flow time withspecific areas of the patient's nose (e.g., septum).

In an embodiment, the ball-type insert 2338 may have a sphere-like shapeand may include one or more perforations, grooves, dimples, or detentsalong its exterior surface. However, the ball-type insert 2338 may haveother suitable shapes, e.g., non sphere-like.

In an embodiment, a connector 2338(1) may be provided between ball-typeinserts 2338 of adjacent prongs to prevent discharge of the inserts 2338through respective orifices.

It should be appreciated that the ball-type insert 2338 may be adaptedfor use with dual-wall nasal prongs.

1.6.4 One-way Valve

In another embodiment, a one-way valve may be provided to the ventarrangement of the nasal prong assembly to reduce the pressure ofexhalation and allow easier nose breathing. The one-way valve is adaptedto pivot or otherwise move between (1) an open position that uncoversthe vent arrangement to allow venting during exhalation, and (2) aclosed position that covers at least a portion of the vent arrangementduring inhalation. The valve may provide variable vent flow in theclosed position, e.g., depending on closed portion of vent arrangement.The threshold pressure may be set at therapy pressure, such that thevalve moves to the open position during exhalation as added pressurefrom the patient's lungs exceeds therapy pressure.

1.6.5 Blocking Flap

FIGS. 5-22-1 and 5-22-2 illustrate a nasal prong assembly 2420 accordingto another embodiment of the present invention. As illustrated, thenasal prong assembly 2420 includes a base 2422 and a pair of nasalprongs 2424 provided to the base.

In the illustrated embodiment, a blocking flap or valve 2447 may beprovided to one or both ends of the base 2422 (e.g., depending onwhether air enters the base via one or both ends) to control the flow ofair entering the base 2422 and hence the pair of nasal prongs 2424. Asillustrated, the blocking flap or valve 2447 is adapted to pivot orotherwise move between (1) an open or partially open position thatuncovers at least a portion of the end of the base to allow pressurizedair to enter the base during inhalation (see FIG. 5-22-1), and (2) aclosed position that blocks or covers the end of the base to preventpressurized air from entering the base during exhalation and venting(see FIG. 5-22-2). This arrangement is adapted to block incoming flowfrom the PAP device on exhalation to reduce the pressure of exhalationand allow easier nose breathing.

In an alternative embodiment, a vibratable flap may be provided alongthe flow path to introduce random diffuse of air.

1.6.6 Change Frequency

In another embodiment, the prong may be configured to change frequency,e.g., like jet engine.

1.6.7 Common Stalk

FIGS. 5-23-1 and 5-23-2 illustrate a nasal prong assembly 2520 accordingto alternative embodiments of the present invention. As illustrated,each nasal prong assembly 2520 includes a base 2522, a pair of nasalprongs 2524, and a common support or stalk 2523 that interconnects theprongs 2524 with the base 2522.

In FIG. 5-23-1, each prong 2524 includes a relatively short stalk 2527provided to the common stalk 2523. In use, the common stalk 2523 and/orthe relatively short stalk 2527 may provide a trampoline or bounceeffect.

In an alternative embodiment, as shown in FIG. 5-23-2, the relativelyshort stalk may be eliminated and each prong 2524 may be directlycoupled to the common stalk 2523. In such embodiment, the common stalk2523 may provide a trampoline or bounce effect.

1.6.8 Nasal Insert

FIGS. 5-24-1 and 5-24-2 illustrate nasal inserts 2624 according toalternative embodiments of the present invention. In use, the nasalinsert 2624 is inserted into the patient's nasal passage and retainedtherein by inflation of the outer wall 2628.

As illustrated, the nasal insert 2624 includes a dual or double-wallarrangement with an inner wall 2626 and an outer wall 2628 thatsurrounds the inner wall 2626. An air pocket 2648 is provided betweenthe inner and outer walls 2626, 2628. In use, air enters the pocket 2648to inflate the outer wall 2628 or cause the outer wall 2628 to bulgemore outwardly. Such arrangement allows the outer wall 2628 to seal andconform within the patient's nasal passage.

As shown in FIG. 5-24-1, the insert 2624 may provide an open endedpocket wherein air is adapted to enter the pocket 2648 via the openingbetween free ends of the inner and outer walls 2626, 2628.

Alternatively, as shown in FIG. 5-24-2, the insert 2624 may provide aclosed pocket wherein air is adapted to enter the pocket 2648 via one ormore openings 2636 provided through an intermediate portion of the innerwall 2626.

1.6.9 Alternative Embodiments

The following figures illustrate embodiments structured to improve seal,stability, and/or comfort, for example.

FIG. 5-25 illustrates a nasal prong 2724 according to another embodimentof the present invention. As illustrated, the nasal prong 2724 includesa dual or double-wall head portion. Specifically, the head portionincludes an outer wall 2728 and an inner wall 2726 that is invertedinternally or looped over at the top of the outer wall 2728 to form thedual wall construction. This arrangement provides a rounded top tostrengthen the top which may facilitate insertion of the prong 2724 intoengagement with the patient's nostril. That is, this arrangementprovides one continuous wall that is engaged with the nostril, ratherthan two separate walls such as embodiments of the dual wallconfigurations described above. Such arrangement may also enhance theseal of the head portion and may reduce the time of mask set-up as thedual wall configuration provides more ability to seal.

FIG. 5-26 illustrates a dual wall nasal prong 2824 according to anotherembodiment of the present invention. As noted above, the outer wall maybe relatively thin to enhance conformance to the patient's nasalcontours. In the illustrated embodiment, the rim 2828(1) of the outerwall 2828 may be thicker or more rigid to stiffen the top of the outerwall 2828, e.g., to prevent creeping out of the outer wall as indicatedin dashed lines. However, the outer wall 2828 may include other supportstructures or mechanisms to stiffen the outer wall and/or enhance theseal, e.g., ribs as described above.

FIG. 5-27 illustrates a dual wall nasal prong 2924 according to anotherembodiment of the present invention. In the illustrated embodiment, theouter wall 2928 loops over or rolls over the inner wall 2926. That is,the outer wall 2928 provides a rolled edge 2928(1) that rolls or curlsinwardly and at least partially into the orifice of the inner wall 2926.A gap is provided between the free ends of the inner and outer walls2926, 2928. The rolled edge 2928(1) may taper towards its free end. Thisarrangement provides a rounded top to strengthen the top to facilitateinsertion in use, e.g., similar to the prong shown in FIG. 5-25. Also,this arrangement holds the outer wall 2928 and prevents pullingside-to-side.

FIG. 5-28 illustrates a dual wall nasal prong 3024 according to anotherembodiment of the present invention. As illustrated, the outer wall 3028is inverted externally or looped over at the top of the inner wall 3026to form the dual wall construction. This arrangement provides a roundedtop to strengthen the top to facilitate insertion in use, e.g., similarto the prong shown in FIG. 5-25. In an alternative embodiment, the outerwall 3028 may be inverted internally. Pressurized air may help tomaintain the form of the prong in use.

FIG. 5-29 illustrates a dual wall nasal prong 3124 according to anotherembodiment of the present invention. As illustrated, the outer wall 3128is inverted externally or folded outwards over the outside of the innerwall 3126 to form the dual wall construction. This arrangement providesa rounded top or rolled over end to facilitate insertion in use. In theillustrated embodiment, the inner and outer walls 3126, 3128 are bentand/or contoured along their length to provide flexibility in use.Pressurized air may help to pull the inner wall 3126 into the patient'snose in use.

FIG. 5-30 illustrates a nasal prong 3224 according to another embodimentof the present invention. As illustrated, the stalk 3227 of the nasalprong includes a gusset portion or flexing detail 3233 to addflexibility and articulation of the nasal prong in use. That is, thegusset portion 3233 may facilitate bending, stretching, and/orcompressing of the nasal prong in use. Such arrangement may improve sealand stability of the prong in use. Pressurized air may expand the gussetportion 3233 so that it increases the projected surface area on thepatient's nose, e.g., to improve seal.

FIG. 5-31 illustrates a nasal prong assembly 3320 according to anotherembodiment of the present invention. As illustrated, the stalk 3327 ofeach prong 3324 is sunken, recessed, or inset into the base 3322 todefine a recess 3349 surrounding the stalk 3327. Such arrangementincreases the length/height of the prongs 3324 (e.g., add extra lengthto the stalks 3327) without increasing the overall height of the prongs3324 with respect to the base 3322. In addition, the interface betweeneach stalk 3327 and the base 3322 provides a trampoline or bounceeffect. This arrangement allows greater extension, compression, androtation of each prong to facilitate sealing in use. In addition,extension, compression, and rotation of the prongs (as indicated by thearrows in FIG. 5-31) acts as a form of “suspension” so that the base3322 can move away from the prongs without disrupting the seal. Further,the recessed suspension arrangement allows the patient's fingers toreach underneath the prongs 3324 in order to adjust them in the nose inuse.

In an embodiment, the prongs may be molded in one piece with the base,and the recess surrounding each prong is exposed to the molding tool'sopen and shut direction, e.g., to avoid an undercut.

FIGS. 5-32-1 to 5-32-5 illustrate a nasal prong 3424 according toanother embodiment of the present invention. As illustrated, the prong3424 may be formed using an “over-the-center” molding technique whereinthe prong 3424 is molded in an extended position (as shown in FIGS.5-32-1 and 5-32-3) with a detail or over-the-center feature 3439 (e.g.,thin wall) that allows the prong 3424 to sink or be recessed into thebase 3422 (as shown in FIGS. 5-32-2 and 5-32-4). That is, the prong 3424is structured to hold the position shown in FIGS. 5-32-2 and 5-32-4 whenassembled, which is similar to the prongs shown in FIG. 5-31. As notedabove, such arrangement provides a long stalk length and trampoline baseto allow greater articulation (e.g., extension, compression androtation) of each prong in use (e.g., as shown by the rotated prong inFIG. 5-32-5). Also, the recess surrounding each prong 3424 does notinclude an undercut.

FIG. 5-33 illustrates a dual wall nasal prong 3524 according to anotherembodiment of the present invention. As illustrated, the outer wall 3528surrounds and loops over the inner wall 3526. In the illustratedembodiment, both the inner and outer walls 3526, 3528 provide a rollededge 3526(1), 3528(1) respectively that rolls or curls inwardly. Therolled edge 3526(1), 3528(1) may taper towards its free end. Thisarrangement facilitates insertion into the patient's nostrils, and mayprovide a seal with the patient's nostrils that is similar to the sealprovided by dual wall nasal or mouth cushions, e.g., see ResMed'sMirage® mask.

FIG. 5-34 illustrates a nasal prong 3624 according to another embodimentof the present invention. As illustrated, the nasal prong 3624 includesan compression and extension mechanism 3633 to improve flexibility andcomfort of the nasal prong 3624 in use. In the illustrated embodiment,the compression and extension mechanism 3633 is provided to the stalk3627 and includes a bellows or accordion-like configuration withmultiple pleats that allow compression and extension of the prong inuse. Such arrangement provides maximum extensions in a small area.

FIG. 5-35 illustrates a nasal prong 3724 according to another embodimentof the present invention. As illustrated, the nasal prong 3724 includesa recessed trampoline base 3631 such as that shown in FIG. 4-1 describedbelow. In such embodiment, when the prong 3724 has been fullycompressed, the patient's nose may be supported on nose support areasprovided by the base 3722, which provides extra stability in use. Thatis, when the prongs 3724 have been fully compressed, the prongs willtravel with the patient's nose, e.g., if there is mask movement. Asillustrated, each prong has an axis that is angled with respect to acenterline CL of the base.

FIG. 5-36-1 illustrates a nasal prong assembly 3820 according to anotherembodiment of the present invention. As illustrated, a supportstructure, e.g., silicone wings 3845, may extend from the nasal prongassembly 3820 to stabilize or support the nasal prong assembly 3820against the patient's cheek and/or chin.

In an embodiment, as shown in FIG. 5-36-2, a headgear strap 3853 may becoupled to each wing 3845, e.g., via cross-bar 3845(1) or other headgearattachment point provided to the wing, so that tension of the headgearstrap 3853 may press or force the wing 3845 into the patient's face.Moreover, the headgear load or tension is applied to the wing 3845 inorder to take the load off the prongs, i.e., decouple headgear from theprongs. This arrangement facilitates adjustment and improves comfort inthe patient's nostrils.

In an embodiment, headgear straps of headgear may be structured toutilize skeletal features of the patient's face to achieve stability(e.g., increase surface area of straps). For example, as shown in FIG.5-37, the side strap 3953 of headgear and/or a silicone pad provided tothe side strap 3953 may be profiled or contoured to capture the cheekbone of the patient's face in use.

FIG. 5-38 illustrates a nasal prong assembly 4020 according to anotherembodiment of the present invention. As illustrated, a strap 4045 isprovided to the nasal prongs 4024 to link the nasal prongs 4024 andfacilitate adjustment of the nasal prongs 4024 in use. In theillustrated embodiment, the strap 4045 includes a linking member 4045(1)that links the prongs 4024 so that the prongs are connected and supportone another. Also, the strap 4045 includes a finger tab 4045(2) thatprotrudes outwardly from one of the prongs 4024. The free end of thefinger tab 4045(2) may include one or more gripping protrusions 4045(3).In use, the finger tab 4045(2) may pulled and/or pushed to adjust theposition of the prongs 4024 in the patient's nose.

In the illustrated embodiment, the strap 4045 extends along the base ofthe head portion of the prongs 4024. However, the strap may engage theprongs at other suitable locations. In an embodiment, the strap 4045 maybe integrally formed in one piece with the prongs 4024. In analternative embodiment, the strap 4045 be formed separately from theprongs (e.g., from a silicone material with sufficient rigidity to allowpulling/pushing) and attached or retrofit to the prongs 4024. Forexample, the strap 4045 may include spaced openings for receivingrespective prongs 4024 therethrough.

Also, the strap 4045 adds stability to the prongs 4024 by preventingtube drag from pulling prongs out of engagement with the patient's nose.That is, the linking member allows the prong that normally wants to drawout of the patient's nose due to tube drag to be held in place by theother prong.

FIG. 5-39 illustrates a nasal prong assembly 4120 according to anotherembodiment of the present invention. In the illustrated embodiment, agenerally U-shaped inlet tube adaptor 4115 is provided (e.g., retrofit)to the nasal prong assembly 4120 to center the inlet tube 4114 andremove the asymmetric nature of the interface (e.g., inlet tubetypically provided to only one side of the nasal prong assembly). Asillustrated, the inlet tube adaptor 4115 includes side portions 4115(1)adapted to connect to respective ends of the nasal prong assembly 4120and an intermediate portion 4115(2) adapted to connect to the inlet tube4114. In use, gas flows from the inlet tube 4114, into the intermediateportion 4115(2), into the side portions 4115(1), and into respectiveends of the nasal prong assembly 4120. Such arrangement provides asymmetrical configuration to improve stability, e.g., with respect to anasymmetric arrangement wherein an inlet tube is connected to one end ofthe nasal prong assembly. In addition, such arrangement providesflexibility to accommodate different sleep positions, e.g., side ofhead, back of head, etc.

In an alternative embodiment, the tube entry point may be relocated tothe front of the frame for the nasal prong assembly, which may eliminatethe need for plugs, seal rings, etc. In yet another embodiment, acentral soft tube connection may be incorporated into the nasal prongassembly. The soft tube connection may be structured to accommodateflexibility and movement (e.g., increased decoupling of forces) and maybe molded to avoid kinking or reduction of airflow.

FIG. 5-40 illustrates a nasal prong 4224 according to another embodimentof the present invention. As illustrated, the nasal prong 4224 is onesize larger than the typically recommended size. The next larger sizeprong 4224 may be used by educated patients to improve stability as theprong is larger (larger head portion and/or stalk) and requires moreforce to bend or deform it. In addition, the next larger size prong 4224may improve seal and may improve comfort as the next larger size prongprovides a suspension system that allows looser headgear. In anembodiment, at least the head portion of the prong 4224 may include afrosted surface finish to improve comfort, e.g., frosted surface finishlike a lubricated joint that allows sliding.

FIG. 5-41 illustrates a nasal prong assembly 4320 and air deliveryconduit 4314 according to another embodiment of the present invention.In the illustrated embodiment, the air delivery conduit 4314 is in theform of spiral tubing, e.g., similar to spiral configuration of atelephone cord. The use of such spiral tubing 4314 may improve stabilityand help reduce the drag of the tubing on the nasal prong assembly 4320in use.

In the illustrated embodiment, the spiral tubing 4314 is provided to oneend of the nasal prong assembly 4320 for delivering pressurizedbreathable gas. In an embodiment, the spiral tubing 4314 may be springloaded or biased to keep the tubing compact and neat and to preventtangling.

The spiral tubing 4314 may be particularly advantageous for use withsuch nasal prong assembly 4320. Specifically, because tubing for thenasal prong assembly is asymmetric or provided to only one side of thenasal prong assembly, typical elongated tubing (e.g., 2 m elongatetubing) may provide enough pass to pull the nasal prong arrangementsideways (e.g., when the patient moves around in bed) which may breakthe seal between the nasal prongs and the patient's nares. However, thespiral tubing 4314 provides a flexible arrangement that allowssufficient extension and retraction of the tubing in use. Thisarrangement reduces tube drag and effectively decouples the tubing fromthe nasal prong assembly to prevent breaking of the seal.

1.6.10 Foam Prong

In an alternative embodiment, at least a portion of the prong may beconstructed of a foam material. For example, the entire head portion ofthe prong may be constructed of a foam material, and provide a foamcontact surface to interface with the patient's nasal passages. The foamhead portion may provide grip, warming sensation, and/or improvedcomfort in use.

1.6.11 Question-Mark Shaped Prong

In an alternative embodiment, side walls of the prong may include aquestion-mark or sickle shaped configuration.

Alternative Embodiment Nasal Prongs

As shown in FIGS. 16-1 to 16-12, each nasal prong 5024 of nasal prongassembly 5020 includes a head portion 5025 adapted to seal and/orsealingly communicate with a respective patient nasal passage and acolumn or stalk 5027 that interconnects the head portion 5025 with agusset 5022.

In the illustrated embodiment, each head portion 5025 includes a dual ordouble-wall arrangement including an inner wall 5026 (inner membrane orsupport membrane) and an outer wall 5028 (outer membrane or sealingmembrane) that surrounds the inner wall 5026. The outer wall 5028 may berelatively thin (e.g., 0.35 mm) with respect to the inner wall 5026(e.g., 0.75 mm) to conform to the shape of the patient's nose andprovide a more compliant seal.

The stalk 5022 may be relatively short (e.g., about 2-8 mm, e.g., 5.1mm), e.g., due to flexibility provided by the gusset 5022.

1.7 Other Forms of Interfacing Structure

In other forms of the invention, alternative interfacing structures maybe used. For example, a nasal cradle as described in InternationalPatent Application PCT/AU2007/001051, the contents of which are herebyincorporated by cross-reference.

Other alternative forms of interfacing structure could be as describedin U.S. Pat. No. 4,782,832 (Trimble et al.), U.S. Pat. No. 5,724,965(Handke et al.), U.S. Pat. No. 6,119,694 (Correa et al.), U.S. Pat. No.6,431,172 (Bordewick), and International Patent Application WO2000/74758 (Lovell et al.), the contents of each of which is herebyincorporated by cross-reference.

2 Positioning, Suspension & Stabilising

2.1 Introduction

A patient interface in accordance with an embodiment of the inventionprovides a structure for suitable positioning, suspension andstabilizing of the interfacing portion of the patient interface at anentrance to the airways of the patient. This structure includes thestalks of the nasal prongs, the gusset portion, the frame and headgearwith stabilizers. The structure as a whole may be regarded aspositioning the interfacing portions. The stalks of the nasal prongs,and the gusset portion together function as a form of suspension system.The headgear and stabilizers form a structure that resists bending (forexample from tube drag) and yet is flexible to conform to differentfacial geometries, or to move in response to other potentiallydisruptive forces. In combination with the suspension system, a greaterrange of movement of a mask system in accordance with an embodiment ofthe invention can be accommodated without disrupting the seal than inprior art mask systems.

A frame in accordance with an embodiment of the present invention servesa number of functions, including serving as a connection point to whichthe gusset, headgear stabilizers and elbow may be connected. A givenfunctional feature may reside in different structures. For example, thestabilizing portion of headgear may be formed as part of a frame eitheradditionally or alternatively.

2.2 Suspension System

Stalks

As shown in FIG. 4-1, each prong 24 may include a trampoline-likesuspension system at both ends of the stalk 27, such as described in WO2006/130903. Specifically, each prong 24 may include an uppertrampoline-like suspension system 29 between the head portion 25 and thestalk 27, and a lower trampoline-like suspension system 31 between thestalk 27 and the base 22. The upper and lower trampoline-like suspensionsystems 29, 31 act as a universal mechanism to articulate and align thehead portion 25 to the patient's alar and nasolabial angles, self-adjustthe stalk length to suit the patient's nasolabial height, and/or providea comfortable sealing force to the nares. That is, the upper and lowertrampoline-like suspension systems 29, 31 allow rotation of the stalk 27relative to both the head portion 25 and the base 22, and allowreduction in height of the head portion 25 relative to the base 22. Forexample, a relatively thin base may allow the stalk to sink into thebase and/or rotate relative to the base (e.g., like a ball joint), andthe head portion may deform and sink into the stalk (e.g., like a balljoint). Such compliance and flexibility in rotation and height allowsthe range of overall length to be effectively increased or decreased agreat deal to allow for accommodation of different geometries.

In an embodiment, the height H of the stalk 27 may be between 5-15 mm,e.g., 7 mm, 8 mm, 9 mm, 12 mm, etc.

In an alternative embodiment, as shown in FIG. 4-2, the lowertrampoline-like suspension system 31 may include a square edge, e.g.,square edge between bottom of stalk 27 and base 22, to provide asuitable collapsing point for the prong 24 on the base 22. The squareedge may bring the center of articulation down towards the base, whichmay provide more articulation for a particular height of stalk 27.

Gusset

As best shown in FIGS. 16-5, 16-9, and 16-12, the gusset 5022 of nasalprong assembly 5020 includes a base 5023.1 adapted to support the nasalprongs 5024, lateral side walls 5023.2, an outer side wall 5023.3(adapted to face away from the patient's face in use), and an inner sidewall 5023.4 (adapted to face towards and/or contact the patient's facein use).

The gusset 5022 provides structure that creates an axial force toenhance axial or vertical movement (e.g., gusset and prongs (e.g., prongcompression) together can move axially or vertically up to about 17 mm),and provide contact with the patient's upper lip, and create an axialforce to enhance the nasal prong seal. The gusset also allows lateralmovement to enhance stability while maintaining a sufficient seal withan acceptable amount of leak to maintain a sufficient seal (e.g., gussetand prongs (e.g., prong flexibility and dual wall movement) together canmove laterally up to about 7-10 mm total with less than 0.5 L/min leak),provides a trampoline like base due to a relatively thin base (e.g.,0.75 mm) which allows articulation and extra flexibility of the nasalprongs, provides compressibility, and provides a wide range of movementof fit a large range of patients.

The dual wall nasal prongs in combination with the gusset enhances thelateral movement of the nasal prong assembly. Also, each nasal prong mayinclude an upper trampoline-like suspension system between the headportion and the stalk, and a lower trampoline-like suspension systembetween the stalk and the gusset base, which allows rotation of thestalk relative to both the head portion and the gusset base, and allowreduction in height of the head portion relative to the gusset base(e.g., thin gusset base allows retraction of the stalk into the base).

The gusset increases the range of adjustability to substantially preventovertightening of the headgear, e.g., gusset can compress axially toabsorb headgear tension.

As illustrated in FIGS. 16-5, 16-9, and 16-12, the upper portion of thegusset (e.g., base) includes a relatively thinner wall thickness thanthe lower portion of the gusset (e.g., lower portion of the side walls).In an exemplary embodiment, the wall thickness of the upper portion ofthe gusset is about 0.75 mm, and the wall thickness of the lower portionof the gusset is about 1.5 mm. However, other suitable wall thicknessesof the gusset are possible, e.g., to adjust rigidity or springiness. Forexample, in an alternative embodiment, the gusset may include 0.75 mmoverall wall thickness, with selected portions of the gusset includingstiffening members (e.g., ribs) to add rigidity.

As shown in the side view of FIG. 16-9, the gusset 5022 provides a wedgelike cross-section (e.g., wedge angle α of about 15-45° (e.g., 30°) asshown in FIG. 16-9) in which the inner side wall 5023.4 includes alarger surface area than the outer side wall 5023.3. The larger surfacearea of the inner side wall 5023.4 is structured to contact with thepatient's upper lip and tilt the frame and elbow away from the patient'schin and mouth. In addition, this arrangement moves the harder frameedge away from the patient's lip and moves the seal into the patient'snose. The inner side wall 5023.4 may be contoured to match the contourof the patient's upper lip. However, the gusset may have other suitableshapes.

As shown in the front view of FIGS. 16-4 and 16-12, the gusset 5022provides a generally V-shaped cross-section in order to angle the prongsin the correct orientation with respect to the patient's nose.

Combination of Pillows and Gusset

A suspension system combination of pillows and gusset in accordance withan embodiment of the present invention provides significant improvementover related and prior pillows. To facilitate an understanding of thenature of the improvement, it is helpful to consider the following:

To effect an adequate seal against a surface, a system can present aninterfacing component (e.g. the top portion or head of the pillow)against the face (or surface of the nose) with an appropriate force thatrestricts the flow of air between the surface of the face and that ofthe interfacing component. An unnecessarily high level of force is bothuncomfortable and unhealthy—with a range of symptoms from red marks tosores and skin necrosis. Most mask systems use a flexible cushioningmaterial positioned against the skin and located between the skin andmore rigid components of the mask. The cushioning component may bemodeled mechanically as one or more springs.

Generally the spring arrangements of cushions in consideration have arange of possible compression before they are fully compressed or“bottomed out”. Once fully compressed, a cushion will generally havelittle “cushioning” effect, and simply transfer to the face whateverforce has been established through headgear tension. We have discoveredthat it is desirable for improved comfort and seal to provide forsignificantly more movement before a cushion is fully compressed. Aswill be presently described, prior nasal pillow arrangements in masks ofthe presently contemplated type (e.g., Puritan Bennett Adam's Circuit,ResMed Mirage Swift, Innomed Bravo, Respironics Optilife, Fisher &Paykel Opus) provide from about 1 mm to about 6 mm vertical movement,whereas a nasal pillows system according to an embodiment of the presentinvention can provide up to about 10 mm vertical movement before fullycompressing the pillows.

FIG. 23 illustrates the difference between different nasal pillow masksystems. Three mask systems are shown. Each mask system tested generallyprovides two regions, a flatter region and a steep region. In the first,flatter region, the force on the face transmitted through the pillowincreases gradually as the spring is further compressed. Once the springis fully compressed, the force on the face has a much more significantrate of increase. Of the nasal pillow masks tested, the Puritan-BennetBREEZE mask system allows approximately 2 mm of compression before thepillow is fully compressed and the force on the face starts tosignificantly increase. The ResMed SWIFT II allows approximately 6-7 mmof compression before the force on the face starts to increase moresignificantly. Other mask systems tested lie between the BREEZE andSWIFT masks. A mask system in accordance with an embodiment of thepresent invention allows approximately 9-10 mm compression before theforce on the face starts to increase more significantly.

We have also discovered that comfort and seal of a nasal pillows masksystem can be improved if it can accommodated greater lateral movement(e.g., left to right, right to left) without breaking a seal than thatprovided by known nasal pillows mask systems. For example, providinggreater lateral movement facilitates side sleeping. A mask system inaccordance with an embodiment of the present invention providesapproximately five times the lateral movement of SWIFT II withoutunacceptably leaking.

FIG. 24 shows the amount of leak measured for the present example andthe ResMed SWIFT nasal pillow system when subject to lateral movement.The amount of leak increases with the amount of lateral movement.However, since the present example is much more accommodating ofmovement than the SWIFT, at a leak level of approximately 2 L/min,approximately 5 mm of total lateral movement can be accommodated withthe present example compared to approximately 1 mm for the SWIFT mask.The values determined in this test are dependent on the test rig, and inanother test rig, different values may result. Furthermore, the choiceof 2 L/min to measure the amount of movement is somewhat arbitrary andintended merely to illustrate the advantages of the present example.

FIG. 25a to 25g show portions of nasal pillow systems including a rangeof prior art nasal pillows and the present example (FIG. 25g ). Inparticular, they illustrate the portions of the pillows that provide(vertical) compression and lateral movement. As discussed above, theperformance of the different nasal pillows may be modeled as a number ofmechanical springs. The spring constant for a particular spring may be,amongst other things, a function of the material's inherent resilience,the thickness of the part, a radius of curvature, a configuration (e.g.,is the spring a being bent like a cantilever or compressed along itslength) as well as the properties of surrounding components. In thefollowing commentary, the shortcomings of prior nasal pillows will bediscussed as well as how the present example leads to an improvedresult.

FIG. 25a shows a portion of a nasal pillow from the Puritan-BennetBREEZE mask. The pillow includes three apparent corrugations as shown,however, the pillow is mounted in a rigid frame between the bottom twocorrugations, hence the only movement possible in use is that which isafforded by the flexibility of the regions between the top twocorrugations, marked as “flexing” in FIG. 25a . We estimate thatapproximately 2 mm of compression can be provided by the BREEZE pillowbefore it is fully compressed. It is noted that the radius of curvatureof the first curve 25 a-2 and second curve 25 a-4 is approximatelysimilar.

It is noted that U.S. Pat. No. 6,431,172 (Bordewick) appears toillustrate a nasal pillow similar to the BREEZE nasal pillow, howeverinstead of being mounted on a rigid support, it is mounted on aninflatable plenum chamber. As far as we are aware, no commercial samplewas ever produced and hence we are unable to test it. Since the baseregion is described as “entirely flaccid” and “not effective intransmitting forces between nares elements and rigid support” we expectit not to have any “springiness” (or a spring constant with a value ofzero).

FIG. 25b shows a cross-sectional profile of the ResMed SWIFT I and SWIFTII nasal pillows system. As illustrated, the “head” of the pillow cancompress approximately 6 mm before it reaches the base. The first curvedregion 25 b-2 has a generally similar radius as the second curved region25 b-4, however because the second curved region 25 b-4 is adjacent amuch stiffer platform (not shown), the first curved region 25 b-2 ismore flexible than the second curved region 25 b-4.

FIG. 25c illustrates the Fisher & Paykel OPUS nasal pillow. This nasalpillow has a relatively inflexible stalk region. The only compressionthat is provided is by collapse and buckling of the pillow head orcollapse of the stalk base. Because collapse and buckling areunpredictable, this pillow seals very poorly.

FIG. 25d illustrates the Respironics OPTILIFE nasal pillow. Thecorresponding first and second curved regions of this pillow 25 d-2 and25 d-4 have approximately similar radii. The first (25 d-2) of these tworegions is more flexible, in use, very little flexing of the secondregion 25 d-4 appears to occur. Approximately 5 mm compression may beachieved before the stalk is fully compressed. Since the rest of theOPTILIFE pillow is relatively stiff, further compression leads to asignificant increase in force. Note that the sidewall of the pillow baseregion is located below the head region hence, once the stalk region iscompressed (˜5 mm) further compression may only be obtained by bucklingthe pillow.

FIG. 25e illustrates the Innomed BRAVO nasal pillow. This pillow appearsto provide approximately 7 mm of compression before bottoming out. Thepillow has two curved regions 25 e-2 and 25 e-4. The second of these twocurved regions appears to have a larger radius than the first and wewould expect that the region with the larger radius would be moreflexible—everything else being equal. However, since the base region towhich the pillow is connected is relatively stiff, flexing only occursat the first region 25 e-2. Other parts (not shown) of the BRAVO nasalpillows mask adjacent the base of the pillows are constructed from arigid polycarbonate.

A portion of the pillows of the Fisher & Paykel OPUS 2 mask is shown inFIG. 25f . The stalk/neck region of the pillow has two curved portions25 f-2 and 25 f-4. Both curved regions appear to have approximately thesame radius. The pillow appears to provide approximately 6 mm ofcompression before bottoming out. Furthermore, it is noted that the baseregion 25 f-6 of the pillow, is similarly configured to the RespironicsOPTILIFE nasal pillow. Hence, upon compression of the pillow beyond thatprovided by the neck region of the stalk can only be provided bybuckling the pillow, or at least attempting to compress it along itslength.

FIG. 25g shows a portion of a nasal pillow in accordance with an exampleof the invention. First curved region 25 g-2 provides compression of thepillow. Second curved region 25 g-4 has a reduced curvature compared toregion 25 g-2 and hence is stiffer than region 25 g-2. Nevertheless,flexing can still occur at region 25 g-4. Unlike all the prior art nasalpillow regions discussed thus far, the nasal pillow in accordance withan embodiment of the present invention also includes an additionalflexing region 25 g-5 located on a flatter, top or “platform” region 25g-8 of the gusset. The platform region 25 g-8 of the gusset extendsapproximately 5 to 10 mm from the point of connection of the stalk tothe gusset. When the pillow is compressed, this additional flexingregion 25 g-5 can bend somewhat like a cantilever. This contrasts withthe other nasal pillows which may be subject to buckling forces whenfurther compressed.

As shown in FIG. 25g , six flexing regions have been enumerated. Thesemay be named as follows: 25 g-1 “single wall pillow”, 25 g-2 “attachmentof pillow to stalk”, 25 g-3 “stalk”, 25 g-4 “attachment of stalk toplatform”, 25 g-5 “platform” & 25 g-6 “gusset” or “base region”. By wayof comparison of corresponding regions between the SWIFT and the presentexample, the relative stiffness of the different regions is shown inFIG. 26. For example, the stiffness of region 2, the attachment of thepillow to stalk, is approximately the same in the present example andthe ResMed SWIFT. However, in region 4, the attachment of the stalk toplatform is less stiff in the SWIFT than in the present example. Whilethe SWIFT does not have a gusset, a comparison can be made between thebarrel/base region of the SWIFT and the gusset of the present exampleand the result is that the gusset of the present example issignificantly less stiff than the barrel/base portion of the SWIFT.There is a direct inverse correspondence between the amount of movementprovided by stiffness—the stiffer a spring, the less movement isprovided for a given force.

FIG. 27a to FIG. 271 show a nasal pillow and gusset assembly inaccordance with an embodiment of the invention. Some illustrativedimensions are shown. However, it should be noted that the principles ofthe invention may be applied to other sizes and shapes. A preferredplatform region in accordance with an embodiment of the invention has athickness of approximately 0.75 mm and is molded from 40 Shore Ahardness silicone. Other dimensions are as shown.

For example, as shown in FIGS. 27a to 271, D1 may be about 3 mm, D2 maybe about 1 mm, D3 may be about 1 mm, D4 may be about 5 mm, D5 may beabout 2 mm, D6 may be about 3 mm, D7 may be about 4 mm, D8 may be about5 mm, D9 may be about 6 mm, D10 may be about 0.6 mm at the tip, D11 maybe about 20 mm, D12 may be about 7 mm, D13 may be about 5 mm, D14 may beabout 9 mm, D15 may be about 10 mm, D16 may be about 25 mm, D17 may beabout 14 mm, D18 may be about 27°, D19 may be about 32 mm, D20 may beabout 2 mm, D21 may be about 21 mm, D22 may be about 30°, D23 (theaverage outer membrane thickness) may be about 0.35 mm, D24 (the averageinner membrane thickness) may be about 0.75 mm, D25 (the averagethickness of the stalk) may be about 0.75 mm, D26 (the average platformthickness) may be about 0.75 mm, D27 may be about 9 mm, D28 may be about11 mm, D29 may be about 5 mm, D30 may be about 73°, D31 may be a radiusof about 12 mm, D32 may be a radius of about 5 mm, D33 may be about 54mm, and D34 may be about 29 mm. Although specific dimensions areindicated, it is to be understood that these dimensions are merelyexemplary and other dimensions are possible depending on application.For example, the exemplary dimensions may vary by 10-20% or more or lessdepending on application.

As shown in FIG. 27d , the gusset includes a top lip stability region.This portion of the gusset lightly rests on the top lip of the patientin use to aid stability of the system. The area is approximately 5 cm².When compared to the ResMed SWIFT mask (approximately 3.5 cm²), OPUS 1(approximately 2 cm²) and OPUS 2 (approximately 2.5 cm²), this regionhas a relatively larger area, which leads to less pressure on the toplip, and less force concentrations. The exact area in contact with apatient's lip depends on how the mask is positioned in use.

As shown in FIG. 27d , the platform region of the gusset is angled atapproximately 30° with respect to the base of the gusset. See also FIG.28 which is a sketch illustrating the pillows and gusset in use. Byadopting this angled configuration, the risk of frame contacting the toplip is reduced, improving comfort.

FIG. 29 illustrates a nasal pillow according to an embodiment of theinvention (top row) and a prior art arrangement (2nd row). When subjectto a compression force (right hand side), as in when in use, a number ofregions of the present example, such as the platform region begin tobend and flex. However, the same force on the prior art mask assemblyonly results in bending of the region the top of the stalk and the headof the pillow.

Another known form of nasal pillow is described in International PatentApplication No. PCT/AU2006/000770 (Lubke et al., assigned to ResMed)published as WO 2006/130903. This nasal pillow is particularly suitedfor an oro-nasal mask. Because the oro-nasal mask includes nasal pillowsextending from a mouth cushion, they have a significantly longer stalkregion than the nasal pillows discussed above. This long stalkarrangement also provides a significant amount of flexibility andarticulation, however this long-stalk arrangement is a differentconfiguration to the present example. In the present example,significant articulation and movement is provided in relatively shortstalks when compared to the oro-nasal mask of WO 2006/130903.Furthermore, the corresponding top region of the mouth cushion to whichthe long-stalk pillows are connected is relatively stiff compared to thetop region of the present example.

Gusset to Frame Attachment

As shown in FIGS. 16-1 to 16-12, the nasal prong assembly 5020 includesa frame contacting portion 5029 that extends from the lower end of thegusset 5022, and is structured to be removably and replaceably attachedto a frame 5030 (e.g., see FIGS. 15-1 to 15-12), e.g., push-in type fit,tongue/groove mechanical interlock. As illustrated, the frame channel5033 of the frame 5030 is provided along a curve (e.g., see FIG. 15-7).

As best shown in FIGS. 16-5 and 16-6, the frame contacting portion 5029includes an end portion 5029.1 with a sealing lip 5029.2. The endportion 5029.1 is adapted to be easily inserted and retained within theframe channel 5033 (end portion 5029.1 may be tapered to facilitateinsertion). The sealing lip 5029.2 provides a seal around the perimeterof the frame channel 5033 and also in conjunction with the bead 5033.1(see FIGS. 15-9 and 15-12) around the frame channel 5033 retains thenasal prong assembly 5020 onto the frame 5030 during use, as shown inFIG. 17. In addition, such arrangement allows the nasal prong assemblyto be easily disassembled from the frame, e.g., for cleaning orreplacement.

It is noted that, without the sealing lip 5029.2 or bead 5033.1, the endportion 5029.1 would still be able to provide a seal just byinterference of the end portion 5029.1 and the frame. However, thesealing lip and bead arrangement are structured to allow quite a bit ofdisassembly of the nasal prong assembly from the frame without anyincrease in leak. For example, FIG. 16-6-1 illustrates the end portion5029.1 engaged with the frame 5030 (ideal sealed assembly), and FIG.16-6-2 illustrates the end portion 5029.1 partly disassembled from theframe 5030 but the sealing lip 5029.2 remains engaged with the bead5033.1 to maintain seal. In an embodiment, this arrangement may allowthe sides of the nasal prong assembly to lift out of the frame a littlewhile the external catches 6029.3 remain fully engaged with the frame6030 (e.g., see FIG. 16-14-1 described below).

In one form the frame bead 5033.1 has a protrusion in the range of 0.4mm to 1.2 mm, preferably 0.8 mm. The angle of the underside of the beadis preferably in the range 85° to 95°, preferably 90°. Other protrusionvalues and angles are possible. More than one bead may also be used.

As shown in FIG. 17, the sealing lip 5029.2 seals along the inner wallof the frame channel 5033 closest to the internal volume of the frame5030. Any air pressure between the end portion 5029.1 and the inner wallof the frame channel 5033 will enhance the seal as the air pressure willforce the sealing lip 5029.2 into the inner wall of the frame channel5033.

In an embodiment, the end portion 5029.1 of the frame contacting portion5029 may be sufficiently long (e.g., D23 is about 5 mm long) to helplocate the end portion 5029.1 in the frame channel 5033 before aninsertion force is applied to secure the end portion 5029.1 in position.In addition, the end portion 5029.1 may provide only a slight taper sothat the end portion 5029.1 is sufficiently thick to aid insertionand/or to create interference in the channel, increasing retention. Theend portion 5029.1 may also be very long, e.g., the whole depth of theframe channel, to increase retention. This length may vary around theperimeter of the end portion, e.g., only at the front and back, betweenprotrusions 5629.1 (described below), etc.

In an embodiment, the frame contacting portion 5029 and frame channel5033 may provide locating features to properly align the nasal prongassembly 5020 with respect to the frame 5030 and prevent askew assembly.For example, the frame contacting portion 5029 may include one or morecorners/protrusions (example described below) that are adapted to fitinto corresponding recesses provided in the frame channel 5033. However,other suitable locating arrangements are possible.

FIGS. 16-13-1 to 16-13-7 illustrate a nasal prong assembly 5620including a frame contacting portion 5629 with one or more protrusions5629.1 (e.g., four protrusions). When assembled to the frame, the one ormore protrusions 5629.1 are adapted to fit into corresponding recessesprovided in the frame channel to align the nasal prong assembly 5620with respect to the frame (e.g., see recesses 5633.1 in frame 5630 inFIGS. 22-1-2 and 22-1-4 described in greater detail below).

FIGS. 16-14-1 to 16-14-3 illustrate a nasal prong assembly 6020 andframe 6030 according to another embodiment of the present invention. Inthis embodiment, the frame contacting portion 6029 of the nasal prongassembly 6020 includes an external catch or protrusion 6029.3 onopposing sides thereof. When assembled to the frame 6030, the externalcatches 6029.3 are adapted to interlock with corresponding openings6033.1 provided in the frame channel 6033 of the frame 6030. Sucharrangement is structured to improve retention of the nasal prongassembly 6020 to the frame 6030. In addition, the user can visuallyconfirm that the frame/nasal prong assembly are properly connected.Disassembly is relatively easy because the parts are flexible and soft,e.g., disassemble by peeling/pulling nasal prong assembly out of frame.Also, assembly is relatively easy because the frame is sufficientlyrigid, the external catches 6029.3 are sufficiently thick, the frame“window” bar 6033.2 (including thickness t1 plus t2 (see FIG. 16-14-2))is sufficiently flexible and rigid to stretch and snap into place overthe external catch 6029.3 (e.g., see FIGS. 16-14-2, 16-16-1, and16-16-7). As shown in FIG. 16-16-7, the bar 6033.2 may include a chamferc to aid insertion/location of the nasal prong assembly.

FIGS. 16-15-1 to 16-15-10 illustrate the nasal prong assembly 6020. Asillustrated, the nasal prong assembly 6020 includes the gusset 6022, thepair of nasal prongs 6024 provided to the gusset 6022, and the framecontacting portion 6029 extending from the lower end of the gusset 6022.The frame contacting portion 6029 includes four alignment protrusions6029.1 and a sealing lip 6029.2 around its perimeter as described above.In addition, opposing sides of the frame contacting portion 6029 includethe external catch 6029.3 which protrudes outwardly from the bottomedge.

FIGS. 16-16-1 to 16-16-8 illustrate the frame 6030. As illustrated, theframe 6030 includes a main body 6032 with a channel 6033 to retain thenasal prong assembly 6020 and a tube portion 6035 to retain the elbow.Cylindrical connectors 6034 are provided to respective sides of the mainbody 6032 for assembling headgear yoke. Yoke to frame assembly and elbowto frame assembly is described in greater detail below.

Opposing sides of the frame channel 6033 include the opening 6033.1,which extends from the channel to the frame exterior. When the framecontacting portion 6029 is inserted and retained within the framechannel 6033, the external catches 6029.3 protrude through respectiveopenings 6033.1 to the frame exterior. As illustrated, recessed portions6032.1 are provided to the frame exterior adjacent each opening 6033.1,e.g., for tooling. The recessed portions 6032.1 also allow visualfeedback of complete assembly and facilitate access to the catches6029.1 for assembly, e.g., if the catches get stuck.

As shown in FIG. 16-16-7, dimension d is sufficient to allow clearancefor the contacting portion 6029 of the nasal prong assembly. This allowsthe nasal prong assembly to be pushed in far enough for the catch 6029.3to snap past the window bar 6033.2. For the same reason, the catch6029.3 has been design with enough clearance between it and the gusset6022.

FIG. 16-14-3 illustrates a patient interface 6010 including frame 6030,nasal prong assembly 6020, elbow 6040, and headgear including headgearyoke 6055 and straps 6053 (headgear described in greater detail below).

In an embodiment, the nasal prong assembly may be attached to the framein either of two orientations (180° with respect to one another) andthen the headgear must be correctly attached to ensure correctorientation of the nasal prong assembly with respect to the patient'sface in use (e.g., headgear and frame/nasal prong assembly may includemarking to ensure proper assembly/orientation). However, if the headgearis first attached to the frame, then the nasal prong assembly must becorrectly oriented and attached to the frame (same markings apply).

In an alternative embodiment, the patient interface may be structuredsuch that the nasal prong assembly may be attached to the frame in onlyone way and the headgear may be attached to the frame in only one way inorder to ensure correct assembly/orientation (e.g., use mechanicalconstraints such that left side frame to left side yoke only and rightside frame to right side yoke only).

The curved end of the gusset portion (see for example FIGS. 16-4 and 27e) result in the centre of gravity of the nasal mask system being closerto the face of the patient, making the system more stable.

Other gusset to frame mechanisms may be used. See for example thedisclosure of International Patent Application PCT/AU03/00458 publishedas WO 03/090827. Other mechanisms may also be used, for example thatused in the cushion-to-frame mechanism of the Fisher & Paykel OPUS. Inthis case, the orientation of the bead may be perpendicular to theorientation of the illustrated embodiment. In another form, the cushionand frame may be comolded and hence no gusset/cushion to frame mechanismwould be required.

FIGS. 16-17 to 16-39 illustrate gusset-to-frame attachment mechanismsaccording to alternative embodiments of the present invention.

FIG. 16-17 illustrates an arrangement similar to that shown in FIGS.16-14-1 to 16-16-8, i.e., nasal prong assembly 8020 including externalcatch 8029.3 adapted to interlock with corresponding opening 8033.1 inframe 8030. In contrast, the frame 8030 includes little to no recessedportion 8032.1 (e.g., unlike elongated recessed portion 6032.1 in FIGS.16-14-1 to 16-14-3) adjacent each opening 8033.1.

FIGS. 16-18-1 and 16-18-2 illustrate a nasal prong assembly 8120including two external catches 8129.3 on each opposing side thereof thatare adapted to interlock with corresponding openings 8133.1 in the frame8130. As shown in FIG. 16-18-3, the frame 8130 may include ribs 8136along the frame channel 8133 (e.g., on opposing ends and sides of thechannel), e.g., to add rigidity to the frame.

FIG. 16-19 illustrates a single internal catch arrangement. In theillustrated embodiment, the nasal prong assembly 8220 includes a catchon opposing sides thereof (not visible) that are adapted to interlockwith a corresponding internal recess in the frame 8230 (only aprotrusion 8238 providing such internal recess being shown).

FIG. 16-20 illustrates the frame contacting portion 8329 of a nasalprong assembly including an end portion 8329.1 with a sealing lip8329.2. As illustrated, the end portion 8329.1 is sufficiently wide toalways provide an interference fit in the channel 8333 of the frame8330. The bead 8333.1 around the frame channel 8333 also helps retainthe nasal prong assembly onto the frame 8330. In addition, the thicknessof the outer wall 8339 may be increased to enhance interference with theframe contacting portion. In an embodiment, the frame contacting portion8329 may provide about 0.4 mm of interference with the channel 8333.

FIG. 16-21 illustrates a frame 8430 in which an inner wall portion 8435is thickened around its perimeter, e.g., to add rigidity or stiffness.As illustrated, the frame undercut or elbow-to-frame cutout 8437 forretaining the elbow 8440 (e.g., with a snap fit) is maintained wherenecessary. In an embodiment, a clearance c of about 0.2-0.3 mm may beprovided between the elbow 8440 and frame 8430 when connected.

FIG. 16-22 illustrates a frame 8530 in which the snap length of theelbow 8540 is increased to stiffen the inner wall 8535 of the frame8530. That is, the location of the frame undercut or elbow-to-framecutout 8537 for retaining the elbow 8540 (e.g., with a snap fit) ismoved further into the frame 8530.

FIG. 16-23 illustrates a frame 8630 in which the height of the innerwall 8635 is increased to match the height of the frame contactingportion 8629 of a nasal prong assembly. In an embodiment, the height ofthe inner wall may be increased in selected portions of the frame, e.g.,only at opposing front and back portions of the frame.

FIG. 16-24 illustrates a frame 8730 in which the height of the innerwall 8735 is increased to greater than the height of the framecontacting portion 8729 of a nasal prong assembly. In addition, a hookportion 8739 is provided to the inner wall 8735 that is adapted to lockthe frame contacting portion 8729 within the frame channel. In anembodiment, the increased height of the inner wall and hook portion maybe provided in selected portions of the frame, e.g., only at opposingfront and back portions of the frame.

FIG. 16-25 illustrates a frame contacting portion 8829 of a nasal prongassembly in which the stiffness of the sealing lip 8829.2 is increasedby thickening the lip. For example, the sealing lip 8829.2 may bethickened along inner portion A, along upper end portion B, and/or alonglower portion C. In another embodiment, the stiffness of the sealing lip8829.2 may be increased by reducing the length of the lip from the framecontacting portion.

FIG. 16-26 illustrates a frame contacting portion 8929 in which thelength is increased and the sealing lip 8929.2 is moved downwards, e.g.,to lower the engagement point with the frame 8930. To accommodate suchframe contacting portion, the bead 8933.1 around the frame channel 8933is moved downwards, and any frame ribs within the channel are removed orlowered.

FIG. 16-27 illustrates a frame contacting portion 9029 with two sealinglips 9029.2 in series adapted to interface with respective beads 9033.1along the inner wall of the frame 9030.

FIG. 16-28 illustrates a frame contacting portion 9129 with a sealinglip 9129.2 adapted to interface with a bead 9133.1 along an inner wallof the frame 9130 and a recessed portion 9129.5 adapted to interfacewith a bead 9133.2 along an outer wall of the frame 9130. Thepositioning and/or configuration of each lip, recessed portion, and beadmay vary.

For example, in FIG. 16-29, the bead 9133.2 along an outer wall of theframe 9130 may be positioned more downwards within the frame channel andthe corresponding recessed portion 9129.5 may be positioned moredownwards along the frame contacting portion 9129. In FIG. 16-30, theframe contacting portion 9129 includes a sealing lip 9129.2 adapted tointerface with a bead 9133.1 along an inner wall of the frame 9130 and asecond sealing lip 9129.3 adapted to interface with a bead 9133.2 alongan outer wall of the frame 9130. In FIG. 16-31, the frame contactingportion 9129 includes a sealing lip 9129.2 adapted to interface with aninner wall of the frame 9130 and a recessed portion 9129.5 adapted tointerface with a bead 9133.2 along an outer wall of the frame 9130.

FIGS. 16-32 and 16-33 illustrates a frame contacting portion 9229 with asealing lip 9229.2 adapted to interface with a bead 9233.1 along aninner wall of the frame 9230 and a non-slip interface 9229.5 adapted tointerface with an outer wall of the frame 9230. The non-slip interfacemay be barbed (FIG. 16-32), ribbed (FIG. 16-33), or zig-zag, forexample.

In another embodiment, vertical ribs along the channel of the frameand/or along the frame contacting portion of the nasal prong assemblymay be used to create interference for securing the frame contactingportion within the frame channel.

FIG. 16-34-1 illustrates a frame contacting portion 9329 in which theflange length or end portion 9329.1 is extended, e.g., to aid insertioninto the frame channel, to create interference in the frame channel, toincrease retention in the frame channel. This extended length may varyaround the perimeter of the frame contacting portion, e.g., toaccommodate frame ribs within the frame channel. In an embodiment, theextended end portion 9329.1 may include a second sealing lip 9329.3 asshown in FIG. 16-34-2.

FIG. 16-35 illustrates a frame 9330 including a frame channel 9333adapted to accommodate a frame contacting portion of a nasal prongassembly. As illustrated, opposing frame ribs A, B, C, and D areprovided at the base of the frame channel 9333, e.g., to add rigidity tothe frame. In an embodiment, one or more of the opposing frame ribs A,B, C, and D may be removed so that the frame channel can accommodate anextended frame contacting portion 9329 such as that shown in FIGS.16-34-1 or 16-34-2. Alternatively, the frame contacting portion 9329 maybe structured to accommodate one or more of the opposing frame ribs A,B, C, and D.

For example, the frame may only include opposing frame ribs A, and theframe contacting portion may be extended around its perimeter exceptwhere the opposing frame ribs A would be located. In another embodiment,the frame may only include opposing frame ribs A and C (see FIG. 16-36showing frame 9330 with frame ribs A and C only), and the framecontacting portion may be extended around its perimeter except where theopposing frame ribs A and C would be located (see FIG. 16-37 showingframe contacting portion 9329 with cutouts or spaces to accommodateframe ribs A and C). In another embodiment, the frame may only includeopposing frame ribs A, B, and D (see FIG. 16-38 showing frame 9330 withframe ribs A, B, and D only), and the frame contacting portion may beextended around its perimeter except where the opposing frame ribs A, B,and D would be located. In this embodiment, the outer wall of the framemay be thickened where opposing frame ribs C are removed further downinto the frame channel. In yet another embodiment, the frame may notinclude any frame ribs, and the frame contacting portion may be extendedaround its entire perimeter.

FIG. 16-39 illustrates a frame contacting portion 9429 of a nasal prongassembly in which the stiffness of the sealing lip 9429.2 is increasedby filling a gap with silicone 9429.8.

Assembly of Prongs and Gusset

As shown in FIGS. 16-1 to 16-12, the nasal prong assembly 5020 (e.g.,constructed of silicone (e.g., 40 shore A silicone)) includes a gusset5022 and a pair of nasal prongs 5024 provided to the gusset 5022. Thegusset 5022 provides a trampoline-like base which allows movement orflexibility to isolate external forces from the seal (e.g., framemovement does not affect nasal prong seal) and enhance stability, seal,and comfort, as described.

In an embodiment, one or more portions of the exterior surface of thenasal prong assembly 5020 (e.g., the entire exterior surface) may have afrosted or fine surface finish (e.g., sand blasted) in order to reducedust collection.

In an embodiment of the nasal prong assembly (see FIGS. 16-1 to 16-12),D1 may be about 25-35 mm, e.g., 32.3 mm, D2 may be about 15-25 mm, e.g.,20.6 mm, D3 may be about 1-2 mm, e.g., 1.5 mm, D4 may be about 25-35°,e.g., 30°, D5 may be about 10-20 mm, e.g., 13.63 mm, D6 may be about20-30°, e.g., 27°, D7 may be about 5-10 mm, e.g., 7.98 mm, D8 may beabout 5-15 mm, e.g., 10.29 mm, D9 may be about 15-25 mm, e.g., 20.1 mm,D10 may be about 5-10 mm, e.g., 6.99 mm, D11 may be about 3-8 mm, e.g.,4.63 mm, D12 may be about 20-30 mm, e.g., 25.1 mm, D13 may be about 5-10mm, e.g., 8.87 mm, D14 may be about 5-15 mm, e.g., 11.14 mm, D15 may beabout 2-8 mm, e.g., 5.1 mm, D16 may be about 0.5-1 mm, e.g., 0.75 mm,D17 may be about 0.5-1 mm, e.g., 0.75 mm, D18 may be about 65-75°, e.g.,72.5°, D19 may be about 50-60 mm, e.g., 54.37 mm, and D20 may be about25-35 mm, e.g., 28.6 mm, D21 may be about 2-3 mm, e.g., 2.2 mm, D22 maybe about 2-4 mm, e.g., 3 mm, and D23 may be about 4-5 mm, e.g., 4.8 mm.Although specific dimensions and ranges are indicated, it is to beunderstood that these dimensions and ranges are merely exemplary andother dimensions and ranges are possible depending on application. Forexample, the exemplary dimensions may vary by 10-20% or more or lessdepending on application.

In an embodiment, the nasal prong assembly may be provided in multiplesizes, e.g., small, medium, and large.

2.3 Frame

As shown in FIGS. 15-1 to 15-12, the frame 5030 includes a main body5032 and tubular connectors 5034 provided to respective sides of themain body 5032. As illustrated, the frame 5030 provides a relatively anarrow width across the patient's face, e.g., about 45-55 mm (e.g., 48or 49 mm).

Referring to FIGS. 15-8 and 15-10, the main body 5032 includes a channel5033 structured to retain the nasal prong assembly 5020 and anopen-ended tube portion 5035 structured to retain the elbow 5040. Theopen-ended tube portion 5035 protrudes from a frame opening rearwardsinto an internal volume of the frame. Attachment of the elbow 5040 tothe frame 5030 is described in greater detail below.

Each connector 5034 of the frame includes a cavity 5036 having structureto retain respective headgear yoke 5055 of the headgear 5050. Inaddition, the exterior surface of each connector 5034 includes one ormore locking bumps 5038 (e.g., three locking bumps or six locking bumps)adapted to engage ratchet teeth of respective yoke 5055. Attachment ofthe headgear yoke 5055 to the frame 5030 is described in greater detailbelow.

The frame 5030 is constructed of a relatively semi-rigid or soft plasticmaterial (e.g., hard silicone (e.g., 30-80 shore A silicone, preferably70 shore A silicone, or about 60 or 80 shore A silicone), TPE,thermoplastic polyurethanes). As a result, the frame 5030 is relativelysofter and more flexible than the relatively hard plastic material ofthe elbow 5040 and the yokes 5055 of the headgear 5050. The flexibilityof the frame may be adjusted, e.g., frame may have different degrees offlexibility. However, it should be appreciated that the frame may beconstructed of other suitable materials, e.g., harder plastic material.In addition, the frame may have thicker wall section to add hardness.For example, the hardness of the frame material could extend to theShore D hardness scale in the range of 45 to 85, or on the Rockwell Rscale in the range of 50 to 100. It could be made from rubbers,polyurethanes, polyesters, PTFE, polypropylenes and other plastics.

A frame constructed of silicone provides an arrangement that is easierto seal (e.g., with the elbow), and provides no squeak in use (e.g.,when elbow/yokes rotated with respect to frame), without requiring anadditional part and with reduced leak (e.g., effectively zero leak).

In an embodiment of the frame (see FIGS. 15-1 to 15-12), D1 may be about25-35 mm, e.g., 31.7 mm, D2 may be about 15-25 mm, e.g., 19.7 mm, D3 maybe about 45-55 mm, e.g., 48 mm, D4 may be about 35-45 mm, e.g., 39 mm,D5 may be about 25-35 mm, e.g., 28 mm, D6 may be about 20-30 mm, e.g.,26.76 mm, D7 may be about 10-20 mm, e.g., 16.9 mm, and D8 may be about15-25 mm, e.g., 21.06 mm. Although specific dimensions and ranges areindicated, it is to be understood that these dimensions and ranges aremerely exemplary and other dimensions and ranges are possible dependingon application. For example, the exemplary dimensions may vary by 10-20%or more or less depending on application.

Flexibility of the frame allows a given mask system to accommodate arange of different facial geometries, for example ranging from narrower,pointed faces (the so-called “crocodile” or “alligator” shape) to thewider, flatter shape (the so-called “panda” shape). The soft frame isalso aesthetically nicer and soft to touch. The outside surface finishconceals internal details (ribs) and reduces dust. A surface finish maybe applied to inside surfaces also.

2.4 Adjustment

Naso-Labial Angular Adjustment/Yoke to Frame

2.4.1 Headgear/Yoke to Frame Interface

In an illustrated embodiment, headgear is attached to the frame 5030 viaheadgear yoke 5055 (e.g., see FIGS. 19-1 to 19-5). The headgear yoke5055 includes a yoke to frame interface 5085 that is structured toprovide easy assembly to and disassembly from the frame 5030 (e.g.,clear and intuitive assembly, tactile feedback of engagement, easydisassembly for cleaning), retain the frame 5030 during use (e.g.,prevent accidental disassembly during use), provide rotation relative tothe frame 5030, and provide a friction element to provide sufficientrotational torque (e.g., to reduce tube drag, provide tactile/audiblefeedback). In addition, rotation of the frame relative to the yokes doesnot effect impedance.

The frame and nasal prong assembly attached thereto may be rotated withrespect to the yokes positioned on the patient's head to allowadjustment to suit the nasolabial angle for a large range of patients.In addition, such adjustment allows movement of the nasal prongs toavoid air jetting. Because the rotation point RP (see FIG. 13-2) of theyoke to frame interface is spaced sufficiently outwardly from thepatient's nose (e.g., with respect to the yoke 55/frame interfacedescribed above), a degree of rotation of the frame may not effect anequal degree of rotation of the nasal prongs, e.g., not 1:1 rotation.For example, a 5° rotation of the frame may effect a 2° rotation of thenasal prongs.

As best shown in FIGS. 19-5 to 19-7, the yoke to frame interface 5085includes a rear wall 5085.1, an annular side wall 5085.2, and a centralhub 5085.3. The inner edge of the side wall 5085.2 includes a pluralityof ratchet teeth 5085.4 to provide friction and tactile feedback withrespect to the frame. The central hub 5085.3 is tubular with itsinterior cored out/vented. The central hub 5085.3 provides snap fingers5085.5 to retain the interface to the frame 5030 (e.g., three snapfingers), bearing surfaces 5085.6, and a tip extension 5085.7.Supporting ribs 5085.8 extend between the central hub 5085.3 and theside wall 5085.2. In addition, windows 5085.9 are provided in the rearwall 5085.1 to allow molding of the snap fingers 5085.5.

2.4.2 Frame Attachment

As shown in FIG. 19-8, the yoke to frame interface 5085 is structured toattach to a respective connector 5034 of the frame 5030. Each connector5034 of the frame includes a cavity 5036 having structure to retainrespective headgear yoke 5055, i.e., an annular engagement lip 5037.1,yoke snap clearance 5037.2 and yoke tip extension hole 5037.3 toaccommodate the yoke to frame interface 5085, and a bearing surface5037.4. In addition, the exterior surface of each connector 5034includes one or more locking bumps 5038 (e.g., three locking bumps)adapted to engage the ratchet teeth 5085.4 of the yoke to frameinterface 5085.

FIGS. 19-9-1 to 19-9-6 illustrate attachment of the yoke to frameinterface 5085 to a respective connector 5034 of the frame 5030. In FIG.19-9-1, the tip extension 5085.7 of the yoke to frame interface isinserted past the engagement lip 5037.1 on the frame to begin alignment.In FIG. 19-9-2, the yoke snap fingers 5085.5 and frame engagement lip5037.1 contact slightly before contact of the frame bumps 5038 and yokeratchet teeth 5085.4, and the connector 5034 may pull in a little (asindicated by the arrows). In FIG. 19-9-3, as the yoke is insertedfurther, the frame engagement lip 5037.1 is displaced down and theconnector 5034 expands (as indicated by the arrows). Also, the ratchetteeth 5084.4 engage with the frame bumps 5038. In FIG. 19-9-4, the frameengagement lip 5037.1 is folded down almost flat inside the yoke snapclearance 5037.2, and expansion of the frame connector 5034 is limitedby the surrounding yoke side wall 5085.2 (as indicated by the arrows).In FIG. 19-9-5, the front face of the yoke snap fingers 5085.5 and tipextension 5085.7 bottom out inside the yoke tip extension hole 5037.3(e.g., yoke compressed inwards about 1.6 mm beyond nominal position),which provides sufficient space to allow the frame engagement lip 5037.1to relax or resiliently recover to its original position (as indicatedby the arrows). That is, the yoke snap clearance 5037.2 and the yoke tipextension hole 5037.2 is sufficiently long to provide sufficient spacefor the frame engagement lip 5037.1 to recover to its nominal positionfollowing a natural arc, e.g., resiliently pivot back to its nominalposition. In FIG. 19-9-6, the yoke to frame interface 5085 springs backout to a nominal position when the engagement lip 5037.1 relaxes. Asshown in FIG. 19-10, a clearance C1 of at least about 0.5 mm is providedbetween an outer edge of the frame connector 5034 and the yoke to frameinterface 5085.

The snap fingers 5085.5 and tip extension 5085.7 are structured toretain the yoke to the frame, e.g., axial retention and lever retention.In an embodiment, as shown in FIGS. 19-11 and 19-12, the tip extension5085.7 has a length D1 of about 2-4 mm, e.g., 3 mm, each snap finger5085.5 has a diameter D2 of about 6-8 mm, e.g., 7 mm, each snap finger5085.5 has width D3 of about 2-5 mm, e.g., 4 mm, and each snap finger5085.5 provides an engagement face of about 5-15°, e.g., 10°. Althoughspecific dimensions and ranges are indicated, it is to be understoodthat these dimensions and ranges are merely exemplary and otherdimensions and ranges are possible depending on application. Forexample, the exemplary dimensions may vary by 10-20% or more or lessdepending on application.

In an embodiment, the yoke 5055 may be pivoted with respect to the frame5030 without disassembly by an angle D1 of about 5-15°, e.g., due tolever retention and/or frame flexibility.

As shown in FIG. 19-14, the locking bumps 5038 of the frame 5030 and theratchet teeth 5085.4 of the yoke to frame interface 5085 provide aratcheting arrangement to lock the frame/nasal prong assembly in anoperative position. In addition, the ratcheting arrangement provides arotation and sufficient torque arrangement to resist tube drag, andprevent the nasal prongs from being rotated out of the patient's nose,rotate relative to the frame and allow adjustment to suit nasolabialangle, and provide tactile feedback to the user with adjustments.

For example, such arrangement allows 360° rotation of the yoke withrespect to the frame, provides position locks at 15° increments, and thesoft to hard interface (relatively soft frame engages relatively hardyoke) provides tactile feedback to the user with each adjustment.However, the ratchet teeth/locking bumps may be structured to provideother suitable incremental position locks.

The size of the ratchet teeth 5085.4 and locking bumps 5038 may bedetermined by fitting a maximum number of increments (e.g., 6 to 72teeth at 60° to 5° increments, e.g., 24 teeth at 15° increments) arounda minimum diameter. In an embodiment, the length of tooth engagement(i.e., contact length between locking bump and ratchet tooth) may bedetermined by the shallowest point of yoke contacting frame on assembly(e.g., about 2 mm).

FIGS. 19-15-1 to 19-15-5 illustrate rotation of the yoke 5055 withrespect to the frame 5030, e.g., angle adjustment. FIGS. 19-15-1 and19-15-2 illustrate a nominal position of the yoke 5044 and frame 5030.In FIG. 19-15-3, the yoke 5055 is rotated about 3.25° from nominal, andthe frame locking bumps 5038 are deformed sideways and compressedinwards. In FIG. 19-15-4, the yoke 5055 is rotated about 10.75° fromnominal, and the frame locking bumps 5038 are significantly deformedflat by the respective ratchet tooth 5085.4. In FIG. 19-15-5, the yoke5055 is rotated about 15° from nominal, and the frame locking bumps 5038spring back to original form in the next ratchet tooth 5085.4.

It should be appreciated that the torque (e.g., to resist tube drag) maybe adjusted, e.g., torque increased by adding more locking bumps 5038 toframe connectors 5034. Also, instead of a ratcheting type arrangement,other suitable torque arrangements may be provided, e.g., friction-type,magnetic, etc.

In alternative embodiment, the one or more locking bumps of the framemay be separated by truncated or squared-off teeth to allow for easierrotation of the yoke with respect to the frame. For example, FIGS.22-1-1 to 22-1-8 illustrate a frame 5630 and each connector 5634 of theframe 5630 includes locking bumps 5638 (e.g., six locking bumps)separated by truncated teeth 5639 (e.g., see FIG. 22-1-7).

The indents 5639.1 between the locking bumps and the truncated teethmake the locking bumps 5638 longer, meaning that the stress and thuswear on these elements is lower. In addition, as shown in FIGS. 22-1-9and 22-1-10, as the yoke 5655 rotates relative to the frame 5630, eachlocking bump 5638 is displaced sideways. The indent 5639.1 defines aspring relief feature that provides clearance allowing the locking bump5638 to completely flex over on itself. This reduces wear on thesemi-rigid locking bump 5638 over time. The number of locking bumps 5638may be adjusted for desired torque. The cavity 5636 of the connector5634 may be cut out (e.g., by 1 mm) to allow for a snap lock with thecentral hub 5685.1 of the headgear yoke 5655 for tactile connectivity.Attachment of the headgear yoke 5655 to the frame 5630 is described ingreater detail below.

As shown in FIGS. 22-2 and 22-3, the first end portion 5655(1) of eachheadgear yoke 5655 includes a support arm 5680, a yoke to frameinterface 5685 provided to an end of the support arm 5680 and adapted toengage a respective connector 5634 of the frame 5630, and a cheeksupport 5684 (also referred to as a stability arm).

The yoke to frame interface 5685 is structured to provide easy assemblyto and disassembly from the frame 5630 (e.g., clear and intuitiveassembly, tactile feedback of engagement, easy disassembly forcleaning), retain the frame 5630 during use (e.g., prevent accidentaldisassembly during use), provide rotation relative to the frame 5630,and provide a friction element to provide sufficient rotational torque(e.g., to reduce tube drag, provide tactile/audible feedback). Torque isalso provided by interference on the “shaft” between the yoke and theframe, not just the ratchet teeth. For example, FIGS. 22-16-1 and22-16-2 illustrate an embodiment in which the yoke 5655 is structured tohave an interference fit on the shaft 5634.1 of the frame 5630 toprovide torque additional to the ratchet teeth. In an embodiment, theinterference fit may be about 0.4 mm on diameter on the frame shaft,e.g., each d about 0.2 mm in FIG. 22-16-2.

The yoke connection involved in the yoke to frame interface 5685consists primarily of an annular side wall 5685.2, rear wall 5685.3 andcentral hub 5685.1 (e.g., see FIGS. 22-4 to 22-7-8).

The inner radius of side wall 5685.2 has multiple ratchet teeth 5685.4(e.g., 3, 4, 5, or more teeth) to provide friction while allowing forsome rotation of the frame with respect to the yoke (e.g., see FIGS.22-6 and 22-7-8). It should be appreciated that there can be multipleembodiments of ratchet teeth/locking bumps on the yoke/frame, e.g., 24teeth/bumps on frame or yoke adapted to engage 3 or more teeth/bumps onthe other of the frame or yoke. The rotation means the headgear canadapt more readily to the movement of the patient during sleep.Additionally, on the interfacing side of the yoke (i.e., the side of theyoke that sits closest to the patient's skin), the side wall 5685.2extends radially inwards (e.g., by 3 mm) to form a generally C-shapedengagement lip 5685.5 (e.g., see FIGS. 22-4, 22-6, and 22-7-6). This isto allow for a locked horizontally sliding connection with the frameconnector 5634 (direction of sliding connection shown in FIG. 22-2) thatinhibits lateral movement of the yoke and frame so as to prevent theaccidental disassembly of the yoke to frame interface 5685 during use.The tips 5685.5(1) of the C-shaped engagement lip 5685.5 are convexlycurved to provide a lead-in for the frame connector shaft or base5634.1, thereby enabling alignment during assembly (e.g., see FIGS. 22-4and 22-7-6). The width between these two tips 5685.5(1) can be adjustedto vary the force required to assemble to frame and yoke (e.g., if theforce for assembly needed to be adjusted downwards, the distance betweenthe tips 5685.5(1) could be increased).

The central hub 5685.1 (e.g., shown in FIGS. 22-4 to 22-6) is generallycircular and may have a hollow core. The central hub 5685.1 locks withthe cavity 5636 of the frame connector 5634 (e.g., see FIG. 22-12). Thisallows for greater stability when slidingly connected with the frame andalso aids disconnection of the interlocking pieces. When the frameconnector 5634 engages with the central hub 5685.1, there is a snappingsound that aims to provide tactile feedback to the user that the partsare assembled correctly. The central hub 5685.1 is connected to the rearwall 5685.3 via an arm 5685.6 (e.g., see FIGS. 22-4). The posterior sideof the arm 5685.6 can have multiple ribs 5685.6(1) (e.g., 2 or 3 ribs)as shown in FIG. 22-4, that are elevated from the rear wall 5685.3 by,e.g., 2 mm. Ribs 5685.6(1) act to guide the frame into the yoke and thusensure correct assembly of the parts.

The rear wall 5685.3 has a window 5685.7 to allow for unimpeded rotationof the frame with respect to the yoke (e.g., see FIGS. 22-5 and 22-6).It also enables the patient to visually assess if the assembly iscorrect. In addition, the window 5685.7 is provided to mold the ratchetteeth.

FIGS. 22-8 to 22-16 illustrate the attachment of the yoke to frameinterface 5685 to a respective connector 5634 of the frame 5630. InFIGS. 22-8 and 22-9, the frame connector base 5634.1 is inserted pastthe tips 5685.5(1) of engagement lip 5685.5 on the yoke to beginalignment. Ribs 5685.6(1) are also guiding the frame connector 5634 inposition on the anterior side of the connector. FIG. 22-9 demonstratesthe interaction of the central hub 5685.1 with the anterior surface ofthe frame connector 5634 when the parts are not fully engaged. Thecentral hub 5685.1 is flexed outwards about arm 5685.6. FIG. 22-10 is aphotograph of this arrangement.

In FIGS. 22-11 and 22-12, the frame connector base 5634.1 has passedthrough the tips 5685.5(1) of engagement lip 5685.5 on the yoke. Thecentral hub 5685.1 has engaged with cavity 5636 and snapped back fromits flexed position to its original position (as shown in FIG. 22-12).This creates a tactile connection that enables patients to hear when theassembly is correctly joined. Once the connector 5634 has slotted intothe yoke, the locking bumps 5638 engage with the ratchet teeth 5685.4(e.g., demonstrated by FIGS. 22-14 and 22-15). The cavity 5636 of theframe connector 5634 includes a yoke snap clearance 5636.1 that providessufficient space for the central hub 5685.1 to relax or resilientlyrecover to its original position. Similar to window 5685.7, the yokesnap clearance 5636.1 is designed to ensure that there is no impedanceon the rotational motion of the yoke to frame interface 5685 (see FIG.22-12).

FIGS. 22-13 and 22-16 are photographs that show the fully assembledframe 5630 and yoke 5655. Also, FIGS. 22-17-1 and 22-17-2 illustrate theframe 5630 being rotated relative to the yoke 5655.

FIGS. 22-18-1 to 22-18-3 are various views of a mold M for molding theframe 5630 according to an embodiment of the present invention. Asillustrated, the mold M may include upper and lower molds UM, LM formolding the main body of the frame 5630 and side molds SM for moldingthe frame connectors 5634 of the frame 5630. As illustrated, the frame5630 may include draft features (angled surfaces) to facilitate removalfrom the mold M.

FIGS. 22-19-1 to 22-19-7 illustrate the headgear yoke 5655 attached to aheadgear strap 5653, e.g., via stitching, according to an embodiment ofthe present invention. FIGS. 22-20-1 to 22-20-5 illustrate a fullyassembled patient interface 5610 according to an embodiment of thepresent invention. As illustrated, the patient interface 5610 includes aframe 5630 (as described in reference to FIGS. 22-1-1 to 22-1-8), anasal prong assembly 5620 (as described in reference to FIGS. 16-13-1 to16-13-7), an elbow 5740, short tube 5770, and swivel 5790 (as describedin reference to FIGS. 18-8-1 to 18-8-7 and FIGS. 20-5-1 to 20-5-6),headgear including headgear yoke 5655 and straps 5653 (as described inreference to FIGS. 22-2 to 22-19-7), and tube retainer 5561 and headgearbuckle 5560 (as described in reference to FIGS. 5-42-1 to 5-42-6 andFIGS. 5-43-1 to 5-43-7).

FIGS. 22-20-6 and 22-20-7 illustrate the rear or back strap 5657 of thepatient interface 5610. As illustrated, the back strap 5657 includesthinner end portions 5657(1) (e.g., 19 mm width) adapted to engage arespective slotted connector portion of the headgear yoke 5655 and awider intermediate portion 5657(2) (e.g., 38 mm width). The widerintermediate portion 5657(2) includes a slot 5658 which spreads theintermediate portion apart so that it can act like two smaller widthstraps (e.g., 2×19 mm straps), e.g., slot allows the intermediateportion to conform to the back of the patient's head in use. Stressrelease holes 5659 are provided on each of the slot 5658, e.g., so theback strap does not tear. In an embodiment, the slot 5658 is formed by arelatively straight cut between the holes 5659. Also, the back strap5657 may be constructed of a Breathoprene headgear material including anun-broken loop (UBL) side 5660(1) and a Lycra side 5660(2).

FIGS. 22-24 and 22-25 illustrate a yoke to frame attachment mechanismaccording to another embodiment of the present invention. In thisembodiment, at least one yoke and optimally both yokes 7255 are engagedwith the frame 7230 via a ball and socket joint 7285.

The ball and socket joint 7285 allows greater axial rotational and somelateral rotation. A high degree of rotation at the yoke to frameinterface allows the respiratory mask to better accommodate a largerrange of face shapes and sizes. Also, infinite adjustment allows thepatient to have a larger range of motion when using the respiratorymask, while maintaining a comfortable and effective seal. The ball andsocket joint 7285 is a familiar mechanism and visually simple toassemble so therefore more likely to be utilized effectively bypatients.

In the illustrated embodiment, the socket 7210 is provided to the yoke7255 (e.g., integrally formed in one piece therewith) and the ball 7240is provided to the frame 7230 (e.g., integrally formed in one piecetherewith). However, it should be appreciated that the oppositearrangement is possible, i.e., socket on frame and ball on yoke.

As illustrated, the socket 7210 on yoke 7255 is a cavity with agenerally rounded profile. In an embodiment, the socket 7210 is in theshape of a hemisphere. In another embodiment, the socket 7210 is part ofa hemisphere. The socket 7210 may have a lip 7215 on its outer edge asshown in FIG. 22-25, which lip 7215 aids in securely fastening the ball7240 to the socket 7210. The lip 7215 also limits the movement of theframe 7230 beyond desirable limits so that the respiratory mask is ableto maintain its seal. In an alternative embodiment, the socket 7210 mayinclude a lead-in to facilitate connection of the joint.

In an embodiment, the ball 7240 on frame 7230 may be generallyspherical, elliptical, or any other rounded shape. In anotherembodiment, the ball 7240 may be part of a sphere or any rounded shape,e.g., a hemisphere. In yet another embodiment, the ball 7240 may behollow or partly hollow.

In the illustrated embodiment, the ball 7240 may be engaged with thesocket 7210 by a push fit. In an alternative embodiment, the ball 7240may be engaged with the socket 7210 by a sliding connection. In anembodiment, the ball 7240 has the same or larger diameter D than that ofsocket 7210 for an interference fit (e.g., FIG. 22-25 illustrates anembodiment where ball 7240 and socket 7210 have the same diameter D).

In another alternative embodiment, the frame and yoke may be integrallyformed in one piece. In an embodiment, the frame and yoke may includedifferent colors or transparencies with respect to one another.

2.4.3 Yoke to Frame Rotation Indicator

In an embodiment, rotation indicators may be provided on the frameand/or yokes to indicate to the user that the frame can rotate relativeto the yokes. In addition, the rotation indicators may function asposition markings to indicate the frame's position with respect to theyokes, e.g., used as a reference for preferred naso-labial rotationangle.

For example, a series of markings (e.g., dots, arrows, combination ofdots/arrows, etc.) may be provided on the frame that align with aposition mark (e.g., line, dot, arrow, etc.) provided on the yokes toindicate the frame's position.

In FIGS. 19-21-1 to 19-21-3, the frame 5030 includes a series of dots5002 with a center one of the dots (having a larger size) aligned with ahorizontal axis of the frame 5030 (e.g., see FIGS. 19-21-3). In thisembodiment, the dots 5002 are provided on only one side of the frame5030. The adjacent yoke 5055 includes a line 5004 to align with aselected one of the dots 5002 on the frame 5030.

In FIGS. 19-22-1 to 19-22-4, the frame 5030 includes a series of dots5002 with a center one of the dots (having a larger size) offset from ahorizontal axis of the frame (e.g., see FIG. 19-22-4). In thisembodiment, the dots 5002 are provided on both sides of the frame 5030.The adjacent yoke 5055 includes a line 5004 to align with a selected oneof the dots 5002 on the frame 5030. The intent of off-center dots inFIGS. 19-22-1 to 19-22-4 is that the nominal yoke position is indicatedby the large, center one of the dots.

In FIGS. 19-23-1 to 19-23-4, the frame 5030 includes a dot 5002(1)aligned with a horizontal axis of the frame (e.g., see FIG. 19-23-4) andarrows 5002(2) provided on each side of the dot 5002(1). In thisembodiment, the dot/arrows are provided on only one side of the frame5030. The adjacent yoke 5055 includes an arrow 5004 to align with aselected dot/arrow on the frame 5030.

In each embodiment, the markings on the frame and yoke may be printed,molded, etched, polished, etc. Also, the markings on the frame and/oryoke may include other configurations (e.g., color-coded, numbered,varying sizes, bands with ascending heights, etc.). Markings may beprovided on one or both sides of the frame, and markings may be providedon one or both of the yokes. In addition, any suitable number ofmarkings may be provided on the frame and yoke, and the markings mayhave any suitable spacing.

2.4.4 Yoke to Nasal Prong Assembly Rotation Indicator

In an embodiment, rotation indicators may be provided on the nasal prongassembly and/or yokes to indicate to the user that the nasal prongassembly/frame can rotate relative to the yokes. In addition, therotation indicators may function as position markings to indicate thenasal prong assembly's position with respect to the yokes, e.g., used asa reference for preferred naso-labial rotation angle.

For example, a series of markings (e.g., dots, arrows, combination ofdots/arrows, etc.) may be provided on the nasal prong assembly thatalign with a position mark (e.g., line, dot, arrow, etc.) provided onthe yokes to indicate the nasal prong assembly's position.

As best shown in FIGS. 16-15-4 to 16-15-6, the gusset 6022 of the nasalprong assembly 6020 includes a series of dots 6025, e.g., 2, 3, 4 ormore dots. The dots may vary in size, e.g., a center one of the dots(having a larger size) aligned with a horizontal axis of the nasal prongassembly. In this embodiment, the dots 6025 are provided on only oneside of the nasal prong assembly 6020. As best shown in FIG. 22-23-7,the adjacent yoke 6555 includes a protrusion or dot 6504 (may also be inthe form of a line or other suitable alignment indicator) to align witha selected one of the dots 6025 on the cushion 6020.

Similar to the concepts shown in FIGS. 19-21-1 to 19-23-3, the dots 6025featured on the nasal prong assembly 6020 can align with the dot 6504 onyoke 6555 to indicate the position of the nasal prong assembly withrespect to the yoke. This re-positions the patient interface so that itcan have the same settings each time. In an embodiment, the alignmentdot or marker on the yoke may be positioned at any suitable locationalong the arm of the yoke, e.g., closer to the yoke's interface with theframe. Also, in an embodiment, as the yoke is rotated relative to thenasal prong assembly, the yoke may cover one or more of the dots 6025(i.e., instead of alignment markers on the nasal prong assembly and yokemeeting, one may adjust the system until a certain number of dots arevisible, e.g., only 1 or 2 alignment dots are visible).

Another advantage of this alignment concept is it indicates to the userthat the nasal prong assembly should be positioned in the frame in sucha way that the adjacent yoke 6555 with dot 6504 is aligned with dots6025. This therefore indicates that the nasal prong assembly will beoriented so that it interfaces with the nares of the patient correctly,i.e., nasal prong assembly placed in the frame in the right direction.For example, if the patient interface was completely disassembled, it isobvious that the headgear straps are to be placed along the side of theface with the yokes facing outwards. The user would then proceed toconnect the frame to the yokes (which can be put in either way and stillwork). The alignment dots on the nasal prong assembly can then bepositioned so that they are on the side of the yoke with the alignmentdot. This means the nasal prong assembly is in the right direction,i.e., with the largest side of the gusset touching the face of the userand the company logo facing outwards. Should the user attempt to alignthe nasal prong assembly in such a way that the alignment dots on thenasal prong assembly are over the yoke that does not have an alignmentdot, the nasal prong assembly will be facing the wrong way, i.e.,company logo touching the face of the user.

In each embodiment, the markings on the nasal prong assembly and yokemay be printed, molded, etched, polished, etc. Also, the markings on thenasal prong assembly and/or yoke may include other configurations (e.g.,color-coded, numbered, varying sizes, bands with ascending heights,etc.). Markings may be provided on one or both sides of the nasal prongassembly, and markings may be provided on one or both of the yokes. Inaddition, any suitable number of markings may be provided on the nasalprong assembly and yoke, and the markings may have any suitable spacing.

First End Portion, First Embodiment

FIGS. 6-1 to 6-4 illustrate an embodiment of headgear yoke 55. Asillustrated, the first end portion 55(1) includes a yoke ring 56 (alsoreferred to as a retaining member or connector) that is adapted toengage a respective end or connector portion of the frame of the nasalprong assembly 20 (e.g., see FIGS. 2-1 and 2-2). In addition, a sealring or seal portion 58 (see FIG. 1-1) is provided to the yoke ring 56and is adapted to sealingly engage a plug or elbow. Further details ofsuch yoke ring 56 and seal ring 58 (and attachment to a plug or elbow)are described in U.S. Patent Application Publication Nos. 2004-0226566,2006-0137690, and 2005-0241644, each of which are incorporate herein byreference in its entirety.

First End Portion Alternative Embodiment

In the embodiment of headgear yoke 5055 shown in FIGS. 19-1 to 19-5, thefirst end portion 5055(1) includes a support arm 5080, a yoke to frameinterface 5085 provided to an end of the support arm 5080 and adapted toengage a respective connector 5034 of the frame 5030, and a cheeksupport 5084 (also referred to as a stability arm).

Second End Portion, First Embodiment

As shown in FIGS. 1-1, 6-1 to 6-2, and 6-5 for the embodiment ofheadgear yoke 55, the second end portion 55(2) provides a slottedconnector portion including a slot 65 that defines a cross-bar 66 thatis adapted to engage a respective end of the rear strap 57.Specifically, a respective end 57(1) of the rear strap 57 may be wrappedaround the cross-bar 66 of the yoke, in a known manner. The free end ofthe rear strap 57 may be tapered (e.g., to aid threading through theslot 65) and secured to the remainder of the strap by a hook and lookarrangement, e.g., Velcro®.

The use of Velcro attachment at the headgear yokes eliminates the use ofa rear buckle to adjust the rear strap 57. This arrangement improvescomfort by removing discomfort and irritation caused by the patientlying on a rear buckle in use.

Second End Portion Alternative Embodiment

As shown in FIGS. 13-1 to 13-4 and 19-1 to 19-4 for the embodiment ofheadgear yoke 5055, the second end portion 5055(2) provides a slottedconnector portion including a slot 5065 that defines a cross-bar 5066that is adapted to engage a respective end of the rear strap 5057.Specifically, a respective end 5057(1) of the rear strap 5057 may bewrapped around the cross-bar 5066 of the yoke, in a known manner. Thefree end of the rear strap 5057 may be tapered and/or locally thinned(e.g., to aid threading through the slot 5065) and secured to theremainder of the strap by a hook and look arrangement, e.g., Velcro®.

In an embodiment, the slot may have a width of about 3-5 mm, e.g., 4 mm,and a length of about 15-25 mm, e.g., 21 mm. However, these dimensionsand ranges are merely exemplary and other dimensions and ranges arepossible depending on application.

Adjustment of Strap Length

Headgear Buckle

As shown in FIG. 1-1, the headgear buckle 60 is adapted to be centrallylocated on the patient's head to allow symmetrical adjustment of theheadgear 50, e.g., adjustment of strap tension can be accomplished bypulling loose tabs on the top of the patient's head in oppositedirections. Specifically, the headgear buckle 60 includes a firstlocking portion 60(1) and a second locking portion 60(2). The firstlocking portion 60(1) is adapted to be removably and adjustably coupledwith one of the upper strap portions 53(1) and the second lockingportion 60(2) is adapted to be removably and adjustably coupled with theother of the upper strap portions 53(1). Each of the upper strapportions 53(1) may be wrapped around the cross-bar of the associatedlocking portion of the buckle, in a known manner. The free ends of theupper strap portions 53(1) may be tapered (e.g., to aid threadingthrough respective locking portions) and secured to the remainder of thestrap by a hook and look arrangement, e.g., Velcro®.

The headgear buckle 60 joins the headgear straps and yokes to form theheadgear, allows fine and infinite adjustments of the headgear straps,allows quick and easy adjustments and loosening of the headgear straps,and/or allows the straps to pull symmetrically against the head tominimize dislodgement of the nasal prong assembly during adjustment.

As noted above, the rear strap eliminates the use of a rear buckle anduses Velcro fasteners, e.g., to improve comfort. Alternative embodimentsto eliminate or reduce discomfort that may be caused by a headgearbuckle include: using an isolated highly elastic section that allows theuser to easily stretch the headgear over the head to remove/replace it;reducing the overall height of the buckle (e.g., low profile buckle);adding padding to the buckle; allowing the user to customize theposition of the buckle so that it can be located on an area of the headthat will not cause irritation to the user (e.g., positioned along sideregions of the head rather than at the back); and/or introducing atextile buckle that provides the same function as a plastic buckle;introducing a headgear material that provides the same function as abuckle.

Soft and Flexible Link

In an alternative embodiment, the headgear buckle may be in the form ofa soft and flexible link (also referred to as a linking element, linkelement or link member). Such a link is disclosed in AustralianProvisional Application No. AU 2008900891, filed Feb. 25, 2008, which isincorporated herein by reference in its entirety. The link provides amore comfortable linking element for headgear straps and has sufficientstrength in tension to secure a mask to a patient's face under pressure.

FIGS. 5-44-1 to 5-44-5 are respectively side, top, longitudinalcross-section, bottom, and isometric views of a link 6134 according toan embodiment of the invention.

In an embodiment of the link (see FIGS. 5-44-1 to 5-44-5), D1 may beabout 0.5-1.5 mm, e.g., 1.0 mm, D2 may be about 1-3 mm, e.g., 2.0 mm, D3may be about 45-50 mm, e.g., 48 mm, D4 may be about 15-25 mm, e.g., 19mm, D5 may be about 20-25 mm, e.g., 23.0 mm, D6 may be about 2-4 mm,e.g., 3.0 mm, D7 may be about 17-22 mm, e.g., 19.5 mm, and D8 may beabout 2-4 mm, e.g., 3.0 mm. Although specific dimensions and ranges areindicated, it is to be understood that these dimensions and ranges aremerely exemplary and other dimensions and ranges are possible dependingon application. For example, the exemplary dimensions may vary by 10-20%or more or less depending on application.

The illustrated link 6134 is formed of a relatively soft and flexiblematerial, preferably an elastomer, e.g., thermoplastic elastomer (TPE),and more preferably a thermoplastic polyester elastomer such as Hytrel™by DuPont Corporation. Alternatively, the link may be constructed from anylon or other material with sufficient strength and flexibility. Thelink may be made by any suitable method, for example by molding.

The illustrated link 6134 may be elongate in the dimension which isadapted to lie parallel to the strap length, and may be approximatelyelliptical in plan view as illustrated (see FIG. 5-44-2).

The link is thin (e.g., less than about 3 mm, and more preferably about0.75 to 2.5 mm thick) in its smallest transverse dimension, and mostlygenerally planar in its unflexed state. Preferably, the link issymmetrical both end-to-end and about a central longitudinal plane, tofacilitate assembly and reassembly of the headgear without needing tohave regard to the orientation of the link. In an embodiment, the linkhas a thickness less than the strap thickness.

The link 6134 has opposed end portions 6136, a pair of transversestrap-receiving slots 6140 and a central portion 6142 between andadjacent the slots. By including a pair of slots 6140 rather than asingle slot, the headgear straps are less prone to skewing in use.

The link of FIGS. 5-44-1 to 5-44-5 is adapted to cooperate with a fabricand foam headgear strap of approximate width 19 mm and approximatethickness 2.7 mm. The illustrated link is approximately 48 mm long by 23mm wide by 1 mm to 2 mm thick. The edges of the link may be rounded.

In the illustrated embodiment, the end portions 6136 (which correspondsubstantially with that part of the link which is overlaid by the strapin use) are approximately 1 mm thick.

The illustrated link further includes a pair of parallel 19 mm by 3 mmtransverse slots 6140 spaced apart by about 3 mm, and a reinforcedcentral portion 6142 adjacent the slots.

It should be appreciated that the link may be adapted for use withheadgear straps of other suitable length, width, and thickness, e.g.,size of slots in link may be sized accordingly to accommodate anysuitable size headgear strap.

In the illustrated embodiment, the central portion 6142 is strengthenedby being thickened relative to the end portions 6136. The reinforcedcentral portion 6142 may comprise an I-shaped thicker region of 2 mmthickness. The center bar 6144 of the I-shape is located between the twoslots and the cross bars 6146 of the I-shape are located between theends of the slots 6140 and the side edge of the link, and taper down inthickness towards their ends.

It will be appreciated that the central portion 6142 may strengthened inways other than by increased thickness, for example by co-molding withdifferent materials, or attachment or inclusion of reinforcing members.

The thickest portion of the link and straps in use is a double thicknessof strap together with a thickness of the end portions 6136. Byproviding a reinforced, thickened central portion 6142, the linkingelement is strengthened without contributing to the overall thickness ofthe assembly of straps and link, since the straps do not wrap around thecentral portion in use. See FIG. 5-45.

FIG. 5-45 is a schematic section of the link 6134 (similar to FIG.5-44-3), showing the location of the rear strap portions 6130 a, 6130 bwhen connected to the link.

As can be seen in FIG. 5-45, the slots 6140 in the link are sized toallow threading of the straps therethrough by the user to adjust theheadgear fit and tension, with the strap ends being doubled back ontothemselves and secured, for example by the use of a hook material 6148(e.g., Velcro™ or similar) stitched or otherwise attached to the endportion of the strap. The strap surface facing the hook tape may have acomplementary loop material attached, or alternatively the hook tape maybe secured against the outer fabric layer of the strap itself.

The link 6134 and strap 6130 are thus adapted to connect together by thestrap making a single pass through the link and forming a U-shape withboth legs of the U parallel to the adjacent surface of the patient'shead.

The thicker portion 6144 of the link 6134 preferably has a thickness ofless than two strap thicknesses, and does not protrude beyond thecombined thickness of the doubled-over strap connected to the link.

In this arrangement, the overall thickness of the strap arrangement isapproximately a double thickness of strap. This contrasts with prior artarrangements where more than a double thickness of strap is located onthe head, for example using a ladder lock, leading to an uncomfortablebulk to lie on. See FIG. 5-46, which shows one end of a prior art ladderlock-type headgear buckle 6200 and strap 6202. Tests have shown that thepressure on a typical head are approximately halved from about 13 g/mm²to about 6 g/mm² when using a link according to an embodiment of thepresent invention.

In accordance with a preferred form of the present invention, a lengthof hook & loop material (e.g., Velcro™) is used to secure an end of astrap to itself and to retain the strap in tension.

The rounded corners of the linking element (see for example FIG. 5-44-2and 5-44-4) reduce the likelihood of a sharp corner impinging on thepatient's head, and lead to improved comfort.

The illustrated arrangement is intended to allow a lower link profileand provide increased comfort to the patient, while retaining the easeof adjustment of current link member designs.

While the illustrated embodiment of the invention is a flexible linkingelement, other forms may be more rigid, or completely rigid.

Such flexible linking element may be used to removably and adjustablycouple upper or top strap portions of headgear (e.g., similar to buckle60 in FIG. 1-1). Also, such flexible linking element may be used toremovably and adjustably couple rear strap portions of headgear (e.g.,see FIGS. 22-23-1 to 22-23-6 described below).

2.5 Side & Rear Stabilising Portions

2.5.1 Headgear

2.5.1.1 Introduction

A mask assembly in accordance with an embodiment of the inventionprovides stability to the interface through a combination of componentsreferred to as “headgear”. The headgear may be broadly described ascomprising a pair of side portions including cheek & upper/crownportions and a rear portion. In the preferred embodiment, the cheekportions include stabilizing features or “yokes”. Furthermore, asdiscussed above naso-labial angular adjustment is provided via a yoke toframe connection mechanism.

As shown in FIG. 1-1, the headgear 50 includes two side portions 52 witha rear portion 54 connecting the side portions 52. Each side portion 52includes a side strap 53 (e.g., constructed of Breathoprene) and aheadgear yoke 55 (e.g., constructed of a molded plastic such as nylon)attached to the side strap 53. The headgear yoke 55 (also referred to asa rigidizer, rigidizing element, stabilizer, stabilizing element,stiffened headgear element) acts as a stiffener or rigidizer to addrigidity to the headgear and add stability to the sides. The rearportion 54 includes a rear strap 57 (e.g., constructed of Breathoprene)that passes around a rear portion of the patient's head (e.g., below theocciput).

Each side strap 53 includes an upper strap portion 53(1) that passesover the top of the patient's head. The upper strap portions 53(1) ofthe side straps 53 are coupled to one another by a headgear buckle 60.The rear strap 57 includes end portions 57(1) coupled to respectiveheadgear yoke 55.

The upper strap portions 53(1) are structured to adjust the sealingforce because they pull the nasal prong assembly 20 up into thepatient's nose. The rear strap 57 is structured to adjust the stabilityof the nasal prong assembly 20 because it pulls the nasal prong assembly20 back into the patient's face on the top lip of the patient.

The headgear 50 captures the crown of the patient's head (whenassembled) while avoiding the base of the neck, accommodates asufficient range of adjustment to cover a broad range of the targetpopulation, and/or provides sufficient flexibility for removal of theinterface without requiring readjustment. In an embodiment, the headgear50 may be provided in multiple sizes (e.g., small, medium, large).

In another embodiment as shown in FIGS. 13-1 to 13-4, the headgear 5050includes two side portions 5052 with a rear portion 5054 connecting theside portions 5052. The headgear 5050 is structured to stabilize thepatient interface on the patient's head and apply sufficient force forsealing. In addition, the headgear is structured to provide one or moreof the functions described below, e.g., unobtrusive, comfortable, easyto use, etc.

Each side portion 5052 includes a side strap 5053 (e.g., constructed ofBreathoprene) and a headgear yoke 5055 (e.g., constructed of hardplastic such as Nylon, Hytrel) attached to the side strap 5053. Theheadgear yoke 5055 (also referred to as a rigidizer, rigidizing element,stabilizer, stabilizing element, stiffener, stiffened headgear element)acts as a stiffener or rigidizer to add rigidity to the headgear and addstability to the sides. The rear portion 5054 includes a rear strap 5057(e.g., constructed of Breathoprene) that passes around a rear portion ofthe patient's head (e.g., below the occiput).

Each side strap 5053 includes an upper strap portion 5053(1) that passesover the top of the patient's head. The upper strap portions 5053(1) ofthe side straps 5053 are coupled to one another by a headgear buckle5060 (e.g., constructed of hard plastic such as Nylon, Hytrel). The rearstrap 5057 includes end portions 5057(1) coupled to respective headgearyoke 5055.

FIGS. 22-21-1 to 22-23-6 illustrate headgear according to anotherembodiment of the present invention. In this embodiment, a rear strapportion is incorporated into each side strap.

Specifically, FIGS. 22-21-1 to 22-21-8 shows a left-hand-side (LHS) sidestrap 6553L with headgear yoke 6555L and FIGS. 22-22-1 to 22-22-8 showsa right-hand-side (RHS) side strap 6553R with headgear yoke 6555R. Eachof the side straps 6553L, 6553R includes an upper strap portion 6553(1)adapted to pass over the top of the patient's head, a front strapportion 6553(2) adapted to pass along the side of the patient's head,and a rear strap portion 6553(3) adapted to pass around a rear portionof the patient's head. As illustrated, each side strap 6553L, 6553R hasa general Y-shape configuration, e.g., similar to headgear in ResMed'sSwift II mask.

FIG. 13-5 is a schematic view illustrating headgear vectors according toan embodiment of the present invention (e.g., in relation to FIGS. 13-1to 13-4 but also applicable to FIGS. 22-21-1 to 22-21-8 for example). Inan embodiment, A1 is about 152°, A2 is about 124°, and A3 is about 84°.However, other dimensions are possible, e.g., depending on application.Such headgear vectors provide stability to the nasal prongs in order tomaintain seal and provide sufficient ear clearance for comfort.

The headgear yoke 6555L, 6555R is substantially similar to the headgearyoke 5655 described above (e.g., see FIGS. 22-7-1 to 27-7-8). Incontrast, the stitching groove 6559 of the headgear yoke 6555L, 6555Rloops around the edge of the second end portion 6555(2) thereof.

In the illustrated embodiment, the upper strap portion 6553(1) and thefront strap portion 6553(2) are formed in one piece, and the rear strapportion 6553(3) is attached to the upper and front strap portions bystitching (e.g., stitch joint indicated at 6556). However, the rearstrap portion 6553(3) may be provided to the upper and front strapportions in other suitable manners, e.g., formed in one piece therewith,attached via adhesive, attached via mechanical connector, etc.

As illustrated, the free end of each rear strap portion 6553(3) includesa Velcro® fastener or tab of hook material 6557. In addition, one sideof each rear strap portion 6553(3) is coated with un-broken loop (UBL)material 6558 (e.g., instead of lycra) which allows the tab of hookmaterial 6557 to fasten anywhere along its length. The tab of hookmaterial 6557 provides an “easy peel” arrangement wherein only a portionof the tab of hook material 6557 engages with the UBL material 6558making it easier to grip.

FIGS. 22-22-9 and 22-22-10 illustrate under-side and top-side views ofthe tab of hook material 6557. The under-side view of FIG. 22-22-9 showsthe UBL side 6558 of the Breathoprene headgear material, Velcro hooks6557(1) of the hook material, and an area 6557(2) with the hooks 6557(1)removed, e.g., to facilitate gripping or peeling the tab. The hooks maybe removed in area 6557(2) through shaving off, ultrasonic removal, orother suitable removal means. The top-side view of FIG. 22-22-10 showsthe Lycra side 6560 of the Breathoprene headgear material (opposite sideof UBL) and the attachment area 6557(3) of the tab to the Lycra side6560. In an embodiment, the tab may be ultrasonically welded to theLycra side 6560.

In use, the upper strap portions 6553(1) of the side straps 6553L, 6553Rmay coupled to one another by a top headgear buckle or link, and therear strap portions 6553(3) of the side straps 6553L, 6553R may becoupled to one another by a rear headgear buckle or link.

For example, FIGS. 22-23-1 to 22-23-6 illustrate a fully assembledpatient interface 6510 with the upper strap portions 6553(1) coupled bytube retainer 5561 and headgear buckle 5560 (as described in referenceto FIGS. 5-42-1 to 5-42-6 and FIGS. 5-43-1 to 5-43-7) and the rear strapportions 6553(3) coupled by linking member 6134 (as described above inreference to FIGS. 5-44-1 to 5-45). In addition, the patient interface6510 includes a frame 6030 and nasal prong assembly 6020 (as describedin reference to FIGS. 16-14-1 to 16-16-8).

In the illustrated embodiment, the headgear yoke is formed separatelyfrom the frame and attached thereto. In an alternative embodiment, theheadgear yoke may be integrally formed with the frame so that the frameand headgear yoke provide a one-piece structure.

The headgear may provide one or more of the following functions: supportand stabilize the nasal prong assembly on the user in a manner thatmaintains the integrity of the nasal prong seal around the naris regionduring the delivery of pressurized air; allow the user to adjust and setthe nasal prong to a desired position to obtain and maintain an “exactfit” with a good nasal prong seal around the naris region during thedelivery of pressurized air; accommodate an anthropometrically diverserange of users (e.g., 95% of male and female population); accommodate arange of different sleeping positions and transitions in sleepingpositions including the ability to support different tube mountingconfigurations (e.g., allow patient to sleep on side without thebarrel-like base and/or prongs being dislodged); allow the user toremove and replace the interface without significant loosening of theadjustment mechanisms; ergonomically comfortable and not a source ofmarking or irritation to the user; unobtrusive and both visually andphysically minimal avoiding the user feeling stifled or claustrophobic;allow the user to wear glasses with the interface; aestheticallypleasing, high quality and stylish; provide a region, or regions, forthe application of branding; allow user to easily assemble/disassemblefrom the nasal prong assembly; and/or allow user to easily fit andremove from head.

2.5.1.2 Headgear Strap Material

In the illustrated embodiment, each of the headgear straps may beconstructed of Breathoprene including an open cell polyurethanelaminated between Lycra outer layers. In alternative embodiments, thenap of the outer layer material may be altered, the density of the corematerial may be altered, and/or the color of the individual materialsmay be altered.

For example, each of the straps may be constructed of micro-fiber nylon(e.g., Tattel), which may provide a relatively soft edge and feel.

However, other suitable materials are possible. In an embodiment, thestraps have a material thickness of about 2-3 mm, e.g., 2.5 mm.

In another embodiment, the straps may be constructed of a more elasticheadgear material to increase decoupling of headgear forces such thatshifts in the headgear position does not significantly influence theseal region.

FIG. 30 is a cross-section of Breathoprene material according to anembodiment of the present invention. As illustrated, the materialincludes a layer L1 of Nylon/Spandex Loop, a layer L2 of Open-cellPolyurethane, and a layer L3 of Polyester/Lycra jersey. The material hasthe benefits of being soft, light, flexible and comfortable. Moisture isallowed to escape through the material from the skin, and air is allowedthrough to maximize heat dispersion and breath-ability, making theheadgear more comfortable to wear for longer periods.

2.5.1.3 Headgear Strap Dimensions and Angles

In an embodiment, an intermediate strap portion 5053(2) of each sidestrap 5053 (e.g., see FIG. 13-2) has a width of about 17-21 mm, e.g., 19mm, and an upper strap portion 5053(1) of each side strap 5053 (e.g.,see FIG. 13-4) has a width of about 17-21 mm, e.g., 19.8 mm. Also, therear strap 5057 may include a central portion with an increased widthsuch that the end portions 5057(1) of the rear strap 5057 (e.g., seeFIG. 13-3) have a width of about 17-21 mm, e.g., 19 mm, and the centralportion 5057(2) of the rear strap 5057 (e.g., see FIG. 13-3) has a widthof about 36-40 mm, e.g., 38 mm. The wider, central portion 5057(2) isadapted to sit further down the back of the patient's head.

As best shown in FIGS. 13-1 and 13-4, the upper strap portion 5053(1) ofeach side strap 5053 is sufficiently long so that the largest patientcan be fitted to the headgear, which results in the upper strap portion5053(1) overhanging at least a portion of the yoke 5055 when fitted to asmaller person. In an exemplary embodiment, the strap length of theupper strap portion 5053(1) (measured from the top of the yoke) may beabout 180-230 mm, e.g., 193 mm.

As best shown in FIG. 13-3, the end portions 5057(1) of the rear strap5057 are sufficiently long so that the largest patient can be fitted tothe headgear, which results in overhang of the end portions 5057(1) whenfitted to a smaller person. In addition, a gap may be provided betweenthe free ends of the end portions 5057(1). In an exemplary embodiment,the strap length of the rear strap 5057 may be about 530-560 mm, e.g.,545 mm.

Velcro Tab

As shown in FIGS. 21-1 and 21-2, a Velcro tab 5059 (hook material) isprovided to the end of each rear strap end portion 5057(1) (see FIGS.13-1 to 13-4) to secure the strap in position. Such Velcro arrangementimproves comfort and usability (locating, pealing, and reattaching). Inaddition, such Velcro arrangement is not visible when the Velcro isattached onto the back strap. In an embodiment, the Velcro provides aneffective engagement area of about 300-500 mm², e.g., 375 mm2. In anembodiment, the rear strap end portion and Velcro tab may have a taperedor triangular shape. In such embodiment, the rear strap may be wider atthe yoke connection, e.g., for stiffness and minimal vertical movement.The central portion 5057(2) may have a reduced thickness with respect tothe remainder of the rear strap, e.g., for increasing pressure forbetter grip.

In an embodiment, the Velcro tab 5059 may be ultrasonically welded tothe rear strap. For example, the Velcro tab 5059 may be ultrasonicallywelded in two locations (see FIG. 21-1) or the Velcro tab 5059 may beultrasonically welded in an enclosed pattern (see FIG. 21-2). However,other suitable attachment methods are possible.

2.5.2 Stabilising Element (Yoke)

Each headgear yoke 55 is constructed from a rigid or semi-rigid material(e.g., injection molded from nylon, polypropylene, polycarbonate, etc.)and attached to a respective side strap 53. The yokes 55 retain at leasta partial portion of the basic shape of the headgear 50, which mayfacilitate donning of the headgear 50.

As shown in FIGS. 1-1 and 6-1 to 6-5, each yoke 55 includes a first endportion 55(1) adapted to secure a respective end of the nasal prongassembly 20 in an operative position, a second end portion 55(2) adaptedto engage a respective end of the rear strap 57, and an intermediateportion 55(3) between the first and second end portions 55(1), 55(2)adapted to add rigidity to a respective side strap 53.

The headgear yokes 55 provide rigidity for stabilizing the interface andflexibility for comfort (when assembled), provide a flexible stiffeningsection for the headgear straps, form a retaining interface with thefirst end portion (yoke ring), and/or provide alignment markers tocorrespond to the correct front-to-back orientation of the nasal prongassembly.

Yoke to Strap Attachment

Each yoke 55 may be attached to a respective side strap 53, e.g., viastitching, welding, gluing, or otherwise mechanically affixed.

In an embodiment, each yoke 55 may be attached to a respective strap 53with glue, e.g., Loctite (e.g. 4011 medical grade). In such arrangement,the glue may be provided along a glue path that is spaced inwardly fromthe side edges of the strap 53 (e.g., 1-5 mm).

In other embodiments, each yoke 55 may be attached to a respective strap53 with double-sided tape, hot melt glue, and/or the application of heat(non glue).

In another embodiment, a sleeve may be created in the side strap 53, andthe yoke 55 may be inserted into such sleeve.

In yet another embodiment, a yoke or rigidizing section may be providedto a respective strap by a manufacturing process. For example, athermoforming process may be used to form a one-piece strap with arigidizing section. In such embodiment, a relatively thick strap may beprovided, and then pressure and/or heat may be applied to the strap incertain sections to add the desired rigidity. In an embodiment, thestrap may be constructed of a foam material that would allow features tobe created in the foam during manufacturing, e.g., seal ring, branding,etc.

In a further illustrated embodiment, each yoke 5055 is attached to arespective side strap 5053 via stitching. As shown in FIGS. 13-1 to 13-4and 19-2, a stitching groove 5058 is provided along a length of the yoke5055 to receive the stitching. As illustrated, the stitching groove 5058is provided along an intermediate portion of the yoke 5055 (e.g., spacedinwardly from the edges).

The stitching groove 5058 locates the stitching making it flush with thetop surface of the yoke, improves aesthetics by providing an overallcleaner appearance, provides a single stitching line to improve comfortlevels through reducing edge stiffness of the headgear strap edge (e.g.,potentially reducing facial marks), and provides path having sufficientlevel of attachment and stability. Also, the recessed structure of thestitching groove 5058 provides a thinner yoke wall section (e.g., seeFIG. 19-20) for the stitching needle to punch through, which providesreduced part deformation.

FIG. 19-19 illustrates exemplary dimensions for an embodiment of thestitching groove 5058. As illustrated, D1 may be about 1-2 mm, e.g., 1.5mm, D2 may be about 0.25-0.75 mm, e.g., 0.4 mm, D3 may be about 1-2 mm,e.g., 1.2 mm, and D4 may be about 25-75°, e.g., 45°. Although specificdimensions and ranges are indicated, it is to be understood that thesedimensions and ranges are merely exemplary and other dimensions andranges are possible depending on application. For example, the exemplarydimensions may vary by 10-20% or more or less depending on application.

It should be appreciated that each yoke 5055 may be attached to arespective side strap 5053 in other suitable manners, e.g., via welding,gluing, or otherwise mechanically affixed.

Yoke Width

In the illustrated embodiment, the yoke 55 includes a width that is lessthan a width of the respective side strap 53, e.g., intermediate portion55(3) narrower than side strap 53.

If stitching is not used to attach the yoke 55 to the respective strap53 (e.g., yoke attached via welding or gluing), the intermediate portion55(3) may be even narrower.

However, in an alternative embodiment, the intermediate portion 55(3)may have a width that is substantially the same as the respective strap53.

In alternative embodiments, the width of the yoke may be tapered orcontoured along its length. For example, FIG. 8-1 illustrates yoke 255that tapers from a smaller width w to a larger width W. FIG. 8-2illustrates yoke 355 that has a convex edge 359 along its length, andFIG. 8-3 illustrates yoke 455 that has a concave edge 459 along itslength.

In yet another embodiment, as shown in FIG. 8-4, one or more slots 561may be provided along a portion of a yoke 555 (e.g., along inner radiusof curved portion of the yoke) to reduce the springboard effect providedby the yoke in use.

In a further illustrated embodiment, the yoke 5055 includes a width(e.g., about 9 mm) that is less than a width of the respective sidestrap 5053 (e.g., about 19 mm), e.g., intermediate portion 5055(3)narrower than side strap 5053. As described above, such arrangement mayeliminate or reduce facial marks in use.

For example, FIG. 19-20 illustrates yoke 5055 attached to strap 5053 bya single stitch 5056. In an embodiment, the cantilever distance D1 isabout 8.5-10.5, e.g., 9.5 mm.

Materials and Properties of stabiliser/Yoke

First Forms

As noted above, each headgear yoke 55 is constructed from a rigid orsemi-rigid material, e.g., nylon, polypropylene, polycarbonate.

In an embodiment, the yoke 55 is sufficiently soft and flexible so thatit can bend or conform to suit the patient's head, and sufficientlyrigid to efficiently transfer headgear forces/vectors for locating thenasal prong assembly 20 on the patient's face.

In another embodiment, the yoke 55 may be rubber like, e.g., constructedfrom Santoprene silicon material or thermoplastic. In anotherembodiment, silicon may be overmolded onto the yokes.

In yet another embodiment, headgear straps may not be provided along theyokes 55, e.g., straps only provided to cup the patient's head.Alternatively, yokes may not be provided.

In yet another embodiment, a flexible connection between the yoke andframe may be provided by an extension of the silicone seal rings, e.g.,to increase decoupling of headgear forces.

In yet another embodiment, a metal component may be inserted in headgearstraps around the yoke region to provide stiffness and to allow the userto customize the headgear region to the shape of the patient's face,e.g., in-molded stainless steel wire. In other forms this insert may beconstructed from a malleable plastic or TPE.

Alternative Forms—Thermoformed Foam Yoke

FIGS. 12-12-1 to 12-13 illustrate headgear with thermoformed foam yoke.

In FIG. 12-12-1, the headgear includes headgear straps 3153 that cup thepatient's occiput and yoke 3155 to couple the headgear straps 3153 withthe nasal prong assembly. The yoke 3155 is constructed of a thermoformedfoam material. Also, a molded plastic seal ring 3156 is provided to aproximal end of the yoke 3155, and a molded plastic buckle 3160 isprovided to a distal end of the yoke 3155 to provide lateral adjustmentwith the headgear straps 3153 (see FIG. 12-12-2).

In an embodiment, the seal ring 3156 and buckle 3160 may be provided tothe yoke 3155 via a thermoformed foam sandwich. For example, FIGS.12-12-3 and 12-12-4 illustrate a thermoforming process for coupling themolded plastic sealing ring 3156 or buckle 3160 to the foam yoke 3155with heat/pressure. As shown in FIG. 12-12-3, a separately moldedrelative hard plastic part (e.g., seal ring 3156 or buckle 3160) ispositioned between two pieces of foam 3155(1), 3155(2), and the plasticring 3156 or buckle 3160 and foam pieces 3155(1), 3155(2) are positionedin a molding tool having a top tool half T1 and a bottom tool half T2.The molding tool is heated up and top and bottom tool halves T1, T2compress the foam pieces 3155(1), 3155(2) and plastic ring 3156 orbuckle 3160 so that the foam pieces 3155(1), 3155(2) bond to one anotherand retain the plastic ring 3156 or buckle 3160 therebetween (see FIG.12-12-4). In another embodiment, the seal ring may be integrated to theyoke.

This embodiment provides increased levels of usability (e.g.,particularly during fitting and adjustment) for intuitive features suchas single piece 3D shaped headgear and lateral headgear tensionadjustments.

Also, this embodiment provides an increased level of aesthetics as itutilizes a thermoformed foam section, which provides broad opportunitiesfor aesthetic styling. In FIG. 12-13, the headgear includes athermoformed foam yoke 3255 with a thin breathoprene layer attachedthereto (e.g., along surface adapted to engage the patient's head inuse) for comfort. Similar to 12-12-1, this embodiment provides increasedlevels of usability (e.g., particularly during fitting and adjustment)for intuitive features such as single piece 3D shaped headgear andlateral headgear tension adjustments.

Branding

Branding may be molded and/or printed onto the yokes 55, and suchbranding may also function as an aid for correct alignment duringassembly. The branding may include changes in color/tone.

Alternative Headgear Yoke

FIGS. 12-1 to 12-4 illustrate alternative arrangements of headgear yoke.Each embodiment may include one or more of the following features:localized thinning to adjust flexibility of the yoke, improved comfort,seal ring co-molded to yoke, improved aesthetics, branding (e.g., toshow which side is inside/outside for assembly), and/or structured tofit more people.

In FIG. 12-1, the yoke 2055 has a streamlined arrangement in which theyoke 2055 includes localized thinning or tapers along its length, e.g.,inner edge of the yoke tapers towards its distal end, to improveflexibility.

FIG. 12-2 illustrates another embodiment of a yoke 2155 having astreamlined arrangement in which the yoke 2155 includes localizedthinning or tapers along its length, e.g., inner edge of the yoke taperstowards its distal end, to improve flexibility. In this embodiment, theyoke 2155 has a smaller width than that shown in FIG. 12-1.

In FIG. 12-3, the yoke 2255 has a geometric or symmetric arrangement inwhich the yoke 2255 has a substantially uniform thickness and shapealong its length. In addition, the distal end of the yoke 2255 includesa section 2280 for branding, e.g., section includes branding cut-out.

In FIG. 12-4, the yoke 2355 has a contoured inner radius or surface andthe distal end of the yoke 2355 includes a section 2380 for branding,e.g., bird logo for aesthetic cues. In an embodiment, a soft elastomericmaterial 2382, e.g., santoprene, may be co-molded to the yoke 2355 alongthe contoured surface. In addition, the branding may include a differentsurface finish than that of the yoke 2355, e.g., elastomeric surface.The embodiment of FIG. 12-4 provides an increased level of aesthetics asit utilizes branding as an aesthetic cue for the design of the yokes.

Flexible Yoke/Incorporated Seal Ring

FIGS. 12-8 to 12-11-2 illustrate headgear with flexible yoke andincorporated seal ring.

In FIG. 12-8, the headgear includes Breathoprene headgear straps 2753and yoke 2755 molded of a thin thermoplastic/silicone material. Asillustrated, the yoke 2755 has a varying profile along its length. Also,a yoke ring 2756 is integrated to the proximal end of the yoke 2755 andbranding 2780 is incorporated into a distal end section thereof. In anembodiment, no headgear straps may be provided along the yoke and a slotmay be provided at the distal end of the yoke for engaging straps thatcup the patient's head.

In FIG. 12-9-1, the headgear includes Breathoprene headgear straps 2853and yoke 2855 constructed of a thin thermoplastic/silicone material. Asillustrated, the yoke 2855 has a general L-shape with a seal ring 2856provided to the proximal end and branding 2880 incorporated into adistal end section. As shown in FIG. 12-9-2, the thermoplastic/siliconeyoke 2855 may include corrugations, arcuate cut outs, thinned outlocalized section, or ridges 2888 to encourage bending or flexing sothat the yoke 2855 can contour to the profile of the user's face (e.g.,similar to swimming goggle straps). The thermoplastic/silicone yoke 2855may maintain strength in the direction of the seal (e.g., into thepatient' nose) which is essentially parallel to the direction of theforce vector created by the straps.

In FIG. 12-10, the headgear includes Breathoprene headgear straps 2953and yoke 2955 constructed of a thin thermoplastic/silicone material. Asillustrated, the proximal end of the yoke 2955 includes a seal ring 2956and the distal end of the yoke 2955 includes a Y-shaped configuration2981. The Y-shaped distal end of the yoke 2955 provides a rigidizeralong two different straps and hence in two different vectors. Also, thestrap portion adjacent the distal end of the yoke 2955 may includesurface texture 2980 for a branding feature.

In FIG. 12-11-1, the headgear includes headgear straps 3053 that cup thepatient's occiput and yoke 3055 to couple the headgear straps 3053 withthe nasal prong assembly. The yoke 3055 includes a narrow constructionand may be formed of a silicone material. As illustrated, the proximalend of the yoke 3055 includes a seal ring 3056 and the distal end of theyoke 3055 includes a cross-bar 3066 for adjustable attachment with theheadgear straps 3053. Also, a foam pad 3090 is provided to the yoke 3055and adapted to contact the side of the patient's face. As shown in FIG.12-11-2, the foam pad 3090 is molded with an undercut so that it canwrap over the yoke 3055. That is, the undercut of the foam pad 3090naturally captures the yoke 3055 and holds the foam pad 3090 in place.

Foam Section Attached to Yoke

In FIG. 12-15-1, the headgear includes headgear straps 3453, moldedplastic yokes 3455 that extend along respective sides of the patient'sface, and a foam section or insert 3490 (e.g, constructed ofviscoelastic foam) attached to the yoke 3455 and adapted to contact theside of the patient's face. As shown in FIG. 12-15-2, the foam section3490 may be molded with an undercut shape so that it can wrap over orcapture the yoke 3455. That is, the molded undercut of the foam section3490 naturally captures the yoke 3455 and holds the foam section inplace. In an embodiment, the undercut shape may be provided to only oneside of the foam section 3490 such as that shown in FIG. 12-15-1.

The viscoelastic foam section 3490 provides a “high comfort” materialaround the sensitive cheek bone (zygomatic) region of the patient'sface, which appears to be one of the primary sources of discomfort forheadgear.

Also, this embodiment provides increased levels of usability (e.g.,particularly during fitting and adjustment) for intuitive features suchas single piece 3D shaped headgear and lateral headgear tensionadjustments.

Silicone/Thermoplastic Foam Attached to Yoke

In FIG. 12-16-1, the headgear includes headgear straps 3553, moldedplastic yokes 3555 that extend along respective sides of the patient'sface, and a foam section or insert 3590 (e.g, injection molded ofsilicone/thermoplastic foam) attached to the yoke 3555 and adapted tocontact the side of the patient's face. As shown in FIGS. 12-16-2 and12-16-3, the silicone/thermoplastic foam section 3590 may be molded withan undercut shape so that it can wrap over or capture the yoke 3555.That is, the molded undercut of the foam section 3590 naturally capturesor slips over the yoke 3555 and retains the foam section 3590 inposition. In addition, this arrangement provides foam to both the insideand outside radii of the yoke 3555. In an embodiment, the foam may bevisco elestic foam and/or may provide heat activated memory.

The silicone/thermoplastic foam section 3590 provides a “high comfort”material around the sensitive cheek bone (zygomatic) region of thepatient's face, which appears to be one of the primary sources ofdiscomfort for headgear.

Also, this embodiment provides increased levels of usability (e.g.,particularly during fitting and adjustment) for intuitive features suchas single piece 3D shaped headgear and lateral headgear tensionadjustments.

2.5.3 Alternative Headgear Yoke

As shown in FIGS. 19-1 to 19-4, each yoke 5055 includes a first endportion 5055(1) adapted to engage a respective side of the frame 5030and provide stability and support to the frame and nasal prong assemblyduring use, a second end portion 5055(2) adapted to engage a respectiveend of the rear strap 5057, and an intermediate portion 5055(3) betweenthe first and second end portions 5055(1), 5055(2) adapted to addrigidity to a respective side strap 5053.

The yokes 5055 include one or more of the following functions: attachheadgear to the frame, provide stability and support to the frame andnasal prong assembly during use, provide a yoke to frame interface,retain the frame during use, easy assembly/disassembly from the frame,rotate relative to the frame and allow adjustment to suit nasolabialangle, durability (e.g., 12 months or more), wide fit range (e.g., 95%of male and female population), visually minimal and unobtrusive,comfortable, provide a region, or regions, for the application ofbranding, and/or ease-of-use.

The yokes 5055 are structured and designed to improve visual integrationand simple clean lines and forms. For example, the contoured form ofeach yoke breaks up flat faces to create highlight/shadow line and givean overall smaller impression. The single stitch and recessed grooveused to attach the yoke to the respective strap provides a clean,streamlined form when assembled. The second end portion of the yoke isstructured to leave minimum edges to lift away from the headgear strapif glued. The overall size of the yoke may be dictated by the variousfunctions of the yoke to frame interface, e.g., minimum overall size andwidth while providing torque and rotation, retention of frame, andsufficient strength in area between yoke to frame and yoke to headgearstrap.

2.5.4 Cheek Support

In accordance with an embodiment of the invention, cheek supports 62 areprovided (e.g., see FIGS. 6-1 to 6-4). These function to enhancestability of the mask system on the face. In one aspect they enableheadgear forces to be directed more onto the front of the face, e.g. themaxilla and or zygoma.

The first end portion 55(1) also includes a curved protrusion in theform of a cheek support 62 that curves forward or inwardly of the yokering 56. The cheek support 62 is attached to an end portion 63 of theside strap 53 (e.g., via stitching, glue, etc.) as shown in FIGS. 1-1and 6-4. The cheek support 62 follows the cheek contour and is adaptedto engage or hug the patient's cheek to provide stable cheek support.That is, the cheek support 62 stably supports the nasal prong assembly20 in position and retains overall sealing stability.

The cheek support 62 provides a feature which both cushions against thecheeks and hugs the face evenly without introducing pressure points.This arrangement may reduce the strap tension required to maintain aseal and optimize patient comfort. Thus, the positioning of the cheeksupports 62 on the headgear yokes 55 should discourage the user fromapplying excess headgear tension or over-tightening of the headgear,which can force the nasal prongs to compress into the naris region andaffect sealing effectiveness.

The cheek supports 62 effectively takes the prongs' responsibility toprovide stability to the mask system. The prongs can hence work almostindependently to the supplied headgear tension, focusing on its ownexpansion to provide a secure seal.

FIG. 6-4 illustrates a version of the cheek support 62 with the strapportion 63 attached thereto. As illustrated, the strap 63 bends aroundthe cheek support 62 to suit the contours of the patient's face. Thecheek support 62 may be flexible or provide a lever action which flexesto suit the patient.

FIGS. 7-1 and 7-2 schematically illustrate how the supplied headgeartension has a different effect on the headgear 50 according to anembodiment of the present invention and ResMed's Mirage Swift headgear150. On the Swift headgear 150, only a small section of the paddedheadgear is used to absorb the headgear tension in order to stabilizethe mask. As a result, a large percentage of the headgear tension isapplied directly through the prongs (see FIG. 7-1), pressing directlyonto the septum and nostrils, which are very sensitive areas. For somepatients, their minimum amount of securing headgear tension issufficient to completely compress the pillows into the nose. Incontrast, the cheek supports 62 on the headgear 50 transfers the bearingsurface area from the prongs such that the headgear tension can bedispersed across the less sensitive cheek area and produce acceptablemask comfort. Beneficially, since mask stability is attributed to theentire headgear, sealing force is left attributed to the prongs. Thus,the cheek supports 62 take in most of the headgear tension, preventingthe prongs from being compressed.

As shown in FIGS. 6-1 to 6-4, rib-strengthened brackets 64 support theyoke ring 56 on the yoke 55. Such brackets 64 add rigidity to the yokering 56 without affecting the flexibility of the yoke 55. That is, thebrackets 64 help retain the yoke ring 56 and hence the frame of thenasal prong assembly 20 in position and prevent the frame fromcompressing the nasal prongs against the naris region when the headgear50 is adjusted/tightened.

In addition, the cheek support 62 and/or brackets 64 may help to reducetube drag which can cause undesired shifting of the frame and/or affectsealing stability.

As shown in FIGS. 13-1 to 13-4, 14-1, and 19-1 to 19-5, each cheeksupport 5084 curves forward of the yoke to frame interface 5085. Thecheek support 5084 is attached to an end portion 5063 of the side strap5053 (e.g., via stitching, glue, etc.). In an embodiment, the endportion 5063 of the side strap 5053 may overhang the cheek support 5084by about 2.5 mm at the tip and about 4.0 mm at the upper and lowersides. However, the strap overhang may have other suitable dimensions,e.g., depending on application, patient comfort, etc.

The cheek support 5084 follows the cheek contour and is adapted toengage or hug the patient's cheek to provide a stable cheek support andhence provide additional support to the patient interface. That is, thecheek support 5084 stably supports the nasal prong assembly 4020 inposition and retains overall sealing stability.

The cheek support 5084 is adapted to rest on the cheeks of the patientin use, e.g., below the cheek bone. Benefits of this location includeone or more of the following: soft skin which is pliable, not sensitive,cheek bone support structure, and/or unobtrusive location.

The curvature of the cheek support 5084 may be determined fromanthropometric analysis to provide a good fit for a wide range ofpatient head sizes. In the illustrated embodiment, the cheek support5084 is raised vertically on the cheek (e.g., by about 2 mm with respectto the cheek support 62 described above) to provide preferred stabilityand comfort for this embodiment of the patient interface.

In an embodiment, the cheek support 5084 may be flexible in order toconform to the contours of the patient's face. Such flexibility may beprovided by the selected material and/or thickness of the cheek support(e.g., 1.2 mm nylon material), and/or the cantilever arrangement of thecheek support (e.g., 22 mm cantilever arm) which may be locally narrowedto aid flexibility.

In an embodiment, as shown in FIG. 19-18, the distance D1 between cheeksupports 5034 may be about 55 mm, which provides a distance D2 of about50 mm with the headgear strap 5053 (e.g., 2.5 mm strap backing on eachside). Such distance provides sufficient clearance to accommodate thewidth of the patient's nose for a wide range of patients, e.g., 97.5%male width is 39 mm (provides over 11 mm clearance). However, suchdistance may be increased, e.g., 60-65 mm distance between cheeksupports.

The cheek supports 5084 provide a three-dimensional gripping mechanism,for sufficient comfort and mask stability, may allow less headgeartension to seal the nasal prongs, and/or may help to reduce tube dragwhich can cause undesired shifting of the frame and/or affect sealingstability. Moreover, the cheek supports 5084 isolate seal forces fromstability forces, so that headgear tension is applied to the cheeksupports rather than to the upper lip and/or to the prongs (preventingthe prongs from being compressed).

In alternative embodiments, more than one cheek support may be provided,and/or the one or more cheek supports may be provided at differentangles.

The support arm 5080 supports the yoke to frame interface 5085 on theyoke 5055. Moreover, the support arm 5080 provides support and stabilityof the frame 5030 and nasal prong assembly 5020 attached thereto.

As shown in FIG. 19-16, the lever length D1 of the yoke 5055 betweenattachment of headgear strap and frame has been increased (e.g., withrespect to the yoke 55 described above). The increase in length providessufficient clearance to accommodate the gusseted nasal prong assembly5020.

As shown in FIGS. 19-1 to 19-5, the support arm 5080 is contoured orc-shaped to strengthen the support arm 5080 along its length.Specifically, the support arm 5080 has a generally C-shapedcross-sectional configuration along its length, which providesstructural rigidity to the support arm 5080 and hence overall stabilityto the yoke 5055. As shown in FIGS. 19-17-1 to 19-17-4 which illustratecross-sections along the length of the support arm 5080, the support arm5080 transitions from a relatively flat section (FIG. 19-17-4) to thethree-dimensional C-shaped section (FIG. 19-17-2). The flat section(FIG. 19-17-4) provides a flat contact surface for engaging therespective headgear strap. The depth of the upper and lower ribs (i.e.,the depth of the upper and lower walls of the c-shaped section) may bedetermined by the width of the gusset 5022 of the nasal prong assembly5020.

Along with the differing structural shape along its length, the wallsection in the support arm 5080 is thicker than the wall section in theremaining portions of the yoke 5055 (e.g., wall section of support arm5080 increases from about 1.2 mm (primary part wall thickness) to about1.5 mm) to provide further rigidity.

The rounded, outwardly facing surface 5080.1 of the support arm 5080(see FIG. 19-2) provides a branding surface for branding, e.g.,lettering and/or logo. Such branding may be molded and/or printed ontothe support arm. However, it should be appreciated that branding may beprovided to other suitable portions of the yoke.

2.5.5 Increase Friction and Stability

The headgear 50 and/or nasal prong assembly 20 may include structure toimprove stability. For example, such structure may increase frictionwith the patient's face, and the added friction enhances stability ofthe mask system on the patient's face in use.

Wider Headgear Straps

In an embodiment, the width of the headgear straps may be increased(e.g., with respect to ResMed's Swift mask) in order to increase thefriction provided by the headgear straps. That is, the straps may bewider to increase the contact area with the patient's face, whichprovides more friction. The added friction increases stability whichimproves comfort. In addition, the wider straps may help to reduceirritation to the patient's cheeks.

FIG. 10-1 illustrates a headgear strap section including a headgearstrap 753 and headgear yoke 755 provided the headgear strap 753 (e.g.,via stitching). In such embodiment, the width w of the strap on eachside of the yoke is about 5-9 mm. In contrast, known embodiments includea strap width on each side of the yoke of about 4.5-5 mm.

FIGS. 10-2-1 and 10-2-2 illustrate another embodiment including widerheadgear straps. In this embodiment, the headgear straps 853 may beconstructed of a foam material to further increase friction. Inaddition, the headgear strap 853 may include an extended portion 863that extends between the nasal prong assembly 820 and the patient'scheek to improve stability.

In an alternative embodiment, the width of the yoke may be thinner inorder to increase the width of the strap on each side of the yoke.

Reduction of Headgear Marking/Irritation

An increase in strap width on a side of the yoke may also help to reduceheadgear “cheek mark”.

In the illustrated embodiment, the headgear closely follows the profileof the patient's face and “hugs” the cheek region. The Breathoprenestraps provide sufficient contact area and friction to stabilize theinterface and the yokes function as a rigid element that retain theshape of the headgear.

A common side effect with known headgear is “cheek mark”, which is atemporary marking left along the side of the patient's face and cheekregion upon removing the interface, after an extended period of wearing.This region R is displayed in FIG. 10-3-1 with respect to ResMed's SWIFTheadgear 150. As illustrated, the temporary marking appears to followthe profile of the headgear straps along the side of the face (e.g.,swoosh mark). Also, yokes attached to the strap by stitching may leave astitch mark and/or indentations along the perimeter of the yoke withstitching indentations on the inside face of the strap material.

According to an embodiment of the present invention, the amount ofheadgear strap material on a side of the yoke facing inwardly (i.e.,towards the patient's nose) may be increased to reduce facial marks leftby the headgear.

FIG. 10-3-2 illustrates a known embodiment in which the width w of thestrap 153 on each side of the yoke 155 is about 5 mm. In sucharrangement, the strap material 153 may cut into the patient's cheek andcreate a cheek mark.

FIG. 10-4 illustrates a headgear section according to an embodiment ofthe present invention in which the strap 953 on the side of the yoke 955facing the patient's nose has a width w of about 8 mm. Such arrangementincreases the cantilever nature of the strap 953 so that the strap 953becomes more flexible and does not substantially cut into the patient'scheek to create a mask.

FIGS. 10-5 and 10-6 illustrate alternative embodiments of headgearstructured to reduce facial marks. In FIG. 10-5, the strap 1053 includesa total width w1 of about 20 mm and includes a width or overhang w2 ofabout 5.5 mm on each side of the yoke 1055. In FIG. 10-6, the strap 1153includes a total width w1 of about 25 mm wide and includes a width oroverhang w2 of about 8.5 mm on each side of the yoke 1155.

Alternative embodiments to eliminate or reduce facial marks occurring onthe cheeks include: reducing the density of the headgear strap material;introducing a softer strap surface material; introducing a highlycompliant element to the inside surface of the strap, removing the sharp90° edge that sits up against the face (e.g., change profile of edge);improving lateral flexibility of the strap and yoke; altering the way inwhich the yokes interface with the frame; imbedding a component ormaterial that provides the function of the yokes within a soft paddedouter layer (e.g., a “sock” like padded outer layer); introducing amaterial that provides flexibility along a single plane/direction (e.g.,it will flex and contour to the shape of the face while providing arigidizer function along an adjustment plane); eliminating the stitchingused to hold the yokes; adding a layer of 3 mm or 4 mm flocking to theinside of the strap; raising the headgear straps off of the face alongthe cheek region so that it is only making contact on the upper lip andside of head; introducing a molded foam component that is transfermolded to a plastic headgear component; reducing the overall materialthickness of the headgear straps; using a thin textile, e.g., linen,rather than a plastic and foam component (e.g., this arrangement mayreduce the overall height of the straps); and/or constructing theheadgear from a thin textile that is stiffened in an isolated region toprovide the rigidizing function currently fulfilled by the yokes (e.g.,stiffening may be provided by impregnating the material with an epoxy(e.g., screen-printing)).

Also, alternative embodiments to eliminate or reduce marking/irritationoccurring on the upper ear lobes include: introducing a lower densitystrap material; altering the geometry of the headgear to avoid the earscompletely; using a softened rounded edge material or soft paddedcomponent where the headgear contacts the ears; providing headgear thatsits over the sides of the ears (e.g., headphone style); incorporating arotational adjustment for the back strap so that the strap can bepositioned to clear the ears; using the ears as a point oflocation/stability (e.g., eye glasses) which may aid in correctlylocating the interface or improving overall stability; and/oreliminating the back strap to avoid the ears.

Friction Pads Provided to Headgear

In another embodiment, a friction pad may be provided to the headgear toincrease friction. For example, FIG. 10-7-1 illustrates a lower headgearstrap section including a headgear strap 1253 and headgear yoke 1255(including yoke ring 1256) provided the headgear strap 1253. Asillustrated, a friction pad 1270 (e.g., constructed of silicone) may beprovided to the yoke 1255 and adapted to contact the patient's cheek orcheekbone region to improve stability and provide additional support tothe seal region.

In an embodiment, such friction pad 1270 may be retrofit to ResMed'sSwift headgear. For example, FIGS. 10-7-2 and 10-7-3 illustrate frictionpads 1270 provided to yokes 155 of ResMed's Swift headgear. In theillustrated embodiment, each friction pad 1270 may include a retainer1271 sized and configured to be accepted in an opening provided in theyoke 155. As illustrated, the friction pads 1270 contour to thepatient's face to improve stability.

Friction Pads Provided to Nasal Prong Assembly

In another embodiment, a friction pad may be provided to the nasal prongassembly to increase friction. For example, FIGS. 10-8-1 to 10-8-3illustrate wings 1372 (e.g., constructed of silicone) provided to thebase or body 1322 of the nasal prong assembly 1320 and adapted tocontact the patient's cheeks or cheekbone region to improve stabilityand provide additional support to the seal region. As shown in FIG.10-8-3, the wings 1372 contour to the patient's face in use.

In embodiments, the wings may extend from the base of the nasal prongassembly or the wings may extend from the frame.

Foam Padding Provided to Headgear

In another embodiment, foam padding may be provided to the headgear toincrease friction. For example, FIG. 10-9-1 illustrates a lower headgearstrap section including a headgear strap 1453 (e.g., constructed ofBreathoprene) and headgear yoke 1455 (including yoke ring 1456) providedthe headgear strap 1453. As illustrated, foam padding 1474 may beprovided to the rear of the strap 1453 and between the strap 1453 andthe yoke 1455.

As shown in FIGS. 10-9-2 and 10-9-3, the foam padding 1474 is suitablycontoured so that the foam padding 1474 guides the strap 1453 along thecurvature of the patient's face to increase surface area and facialcontact provided by the strap 1453, and hence improve stability.

In an alternative embodiment, as shown in FIG. 10-9-4, foam padding maynot be provided between the yoke and the strap. As illustrated, thestrap 1453 may form a wing adapted to engage the patient's face in use.

Alternative Embodiments to Improve Stability

In alternative embodiments, additional support and stability to the sealregion may be provided by wings or straps that sit under the mouth orbelow the chin in use (e.g., chin pad, chin strap).

For example, an exemplary chin strap may follow the plane of theheadgear straps/yokes to run down and under the chin, and such chinstrap may also support a secondary function of holding the mouth closed.

In another embodiment, a loop may contact the patient's face around thenose to provide addition support to the seal region.

Other embodiments to improve headgear stability includes: provideadditional support through adhering the silicone nasal prongs to theskin; provide additional support through increasing contact between theprong and the patient's top lip; provide additional support throughintroducing an inflatable hood to the prongs that expands up against thewalls of the nasal passage to hold the interface in place; provideadditional support through a silicone skeleton that lies across theupper lip and cheek bone region which may eliminate all rigid plasticelements from the face (e.g., headgear may no longer have to function tohold the seal in as this is facilitated by the skeleton, rather theheadgear functions only to hold the skeleton against the face); providegel padding that sits against the face; and/or provide a mouthpiece thatholds the frame in place.

Crown Portion

Crown Strap Style Headgear

FIGS. 12-19 to 12-21-3 illustrate headgear having a crown strap style.

In FIG. 12-19, the headgear includes an arrangement similar to thatshown in WO 2006/130903, which is incorporated herein by reference inits entirety. As illustrated, the headgear includes headgear straps 3853that cup the crown of the patient's head, and yokes 3855 providedbetween the headgear straps 3853 and the nasal prong assembly. Theheadgear straps 3853 include side strap portions 3853(1), bridge strapportions 3853(2), and crown strap portions 3853(3). The side strapportions 3853(1) may provide lateral Velcro adjustment with respect tothe yokes 3855. Also, an additional adjustment buckle may be providedalong the straps at the top of the patient's head. Each yoke 3855includes a yoke ring 3856 to engage the nasal prong assembly and a crossbar 3866 to engage a respective side strap 3853(1).

In FIGS. 12-20-1 and 12-20-2, the headgear is similar to that shown inFIG. 12-19. In contrast, the headgear includes an extra bridge strap.Specifically, the headgear straps 3953 include side strap portions3953(1), upper bridge strap portions 3953(2U), lower bridge strapportions 3953(2L), center strap portions 3953(4) between the upper andlower bridge strap portions, and crown strap portions 3953(3). The sidestrap portions 3953(1) may provide lateral Velcro adjustment withrespect to the yokes 3955. In use, the extra bridge strap may help tobalance headgear forces.

In FIGS. 12-21-1 to 12-21-3, the headgear is similar to that shown inFIGS. 12-20-1 and 12-20-2. In contrast, no center strap portion isprovided between the upper and lower bridge strap portions. Thus, theheadgear straps 4053 include side strap portions 4053(1), upper bridgestrap portions 4053(2U), lower bridge strap portions 4053(2L), and crownstrap portions 4053(3). The side strap portions 4053(1) may providelateral Velcro adjustment with respect to the yokes 4055.

Rear Strap Portion

FIG. 9 illustrates another embodiment of a rear strap 657. Asillustrated, the central portion of the rear strap 657 includes anincreased width w with respect to the end portions. In addition, a hookmaterial 668 is inset from respective ends of the strap 657 (e.g.,attached by welding, stitching, etc.) so that the respective ends of thestrap 657 provide a pull tab 669 to facilitate adjustment. The hookmaterial 668 is adapted to engage remaining portions of the strap (e.g.,loop type material) to secure the strap 657 in position.

Alternative Headgear Materials

FIGS. 12-5 to 12-7-2 illustrate alternative arrangements of headgearmaterial.

In FIG. 12-5, headgear straps 2453 of the headgear are constructed ofBreathoprene material with company branded microfibre 2484 on an insidesurface (i.e., surface adapted to engage the patient's head in use).Similar to FIG. 12-3, the yoke 2455 may include a distal end sectionwith a cut-out logo 2480.

In FIG. 12-6, headgear straps 2553 of the headgear are constructed ofBreathoprene material, and at least a section of the material isperforated 2586. For example, selected portions of the headgear straps2553 may include perforated Breathoprene material, or all the headgearstraps 2553 may include perforated Breathoprene material. Also, athermoformed rigidizer section 2555 may be provided to the headgearstraps 2553, e.g., to secure the nasal prong assembly in position.

In FIG. 12-7-1, the headgear straps 2653 of the headgear are constructedof Breathoprene material, and a heat transfer label 2655 (e.g.,constructed of foam) is provided to each side strap (e.g., label ironedonto strap) to provide a rigidizing function. As shown in FIG. 12-7-2,the heat transfer label 2655 may include corrugations or cut outs 2688to encourage bending or flexing so that the heat transfer label 2655 cancontour to the profile of the user's face. Also, the heat transfer label2655 may provide an opportunity for a wide range of branding designs(e.g., branding printed to label). The seal ring that engages the frameof the nasal prong assembly may be constructed of strap material orsilicone, for example, and provided to the end of the label. In anembodiment, selected portions of the label may be treated.

Removable Foam Sock

In FIG. 12-14-1, the headgear includes headgear straps 3353, moldedplastic yokes 3355 that extend along respective sides of the patient'sface, and a removable sock 3392 (e.g., constructed of foam) thatencloses at least a portion of the yoke 3355. As shown in FIGS. 12-14-2and 12-14-3, the foam sock 3392 may be constructed of open or closedcell foam and forms a sleeve that sheathes or encloses the yoke 3355. Inthe illustrated embodiment, the foam sock 3392 is generally L-shaped,and includes a cut-out 3393 to positively locate and properly positionthe foam sock 3392 with respect to the yoke 3355. The foam sock 3392 maybe a closed cell extruded section or a thin slab of open cell foamrolled back on itself and glued to form the required section. Also, thefoam sock 3392 may be available in a variety of colors and sizes, e.g.,foam sock may extend along portions of the headgear straps and/or nasalprong assembly. In addition, the foam sock 3392 may provide variousaesthetic and branding possibilities.

The foam sock 3392 provides a “high comfort” material around thesensitive cheek bone (zygomatic) region of the patient's face, whichappears to be one of the primary sources of discomfort for headgear.

Tube Retainer

A tube retainer or retaining strap (not shown) may be provided to anupper strap portion 53(1) to retain the air delivery tube when in anupward position along the side of the patient's head (e.g., tuberetainer wraps around both the tube and strap portion or buckle). Anexemplary tube retainer is described in U.S. Pat. No. 7,318,437 and U.S.Patent Application Publication No. 2006-0137690, each of which isincorporated herein by reference in its entirety.

FIGS. 5-47-1 to 5-47-6 illustrate a soft-loop tube retainer 6361according to an embodiment of the present invention. As illustrated, thetube retainer 6361 includes a first strap portion 6361(1) adapted towrap or loop around one of the headgear straps and a second strapportion 6361(2) provided to the first strap portion 6361(1) and adaptedto wrap or loop around the air delivery tube. The tube retainer 6361 maybe provided to the headgear at any suitable position along the upperstrap portions to retain the air delivery tube along the side or overthe top of the patient's head. Also, the tube retainer 6361 may bestructured to wrap or loop around two or more different size tubings,e.g., short tube and 2 m air delivery tube.

In the illustrated embodiment, the tube retainer 6361 is integrallyformed in one-piece (e.g., cut from headgear material (e.g.,Breath-O-Prene™) or other suitable soft and flexible material) with thesecond strap portion 6361(2) extending transverse to the first strapportion 6361(1). As illustrated, the second strap portion 6361(2) isthinner than the first strap portion 6361(1), and each strap portionincludes a Velcro® tab 6362 adapted to secure the respective loop inposition. The first strap portion 6361(1) tapers towards respectiveends, and includes a tab 6363 to facilitate connection with the secondstrap portion 6361(2). FIG. 5-47-6 illustrates the orientation oflooping of the first and second strap portions 6361(1), 6361(2).

In an alternative embodiment, a tube retainer or retaining strap may beprovided to headgear to retain the air delivery tube in a position overthe top of the patient's head (i.e., tube runs over the head as opposedto along the side of the head). This arrangement allows the patient toassume different sleep positions, e.g., sleeping on side head, back ofhead, etc.

For example, a tube retainer or retaining clip may be provided to aheadgear buckle (e.g., in the position of headgear buckle 60 shown inFIG. 1-1 or headgear buckle 5060 shown in FIG. 13-4) to retain the airdelivery tube when in an upward position along the top or side of thepatient's head (e.g., tube retainer clips around the tube and locks intothe strap portion). This arrangement allows the patient to assumedifferent sleep positions, e.g., sleeping on side head, back of head,etc.

In the illustrated embodiment, the tube retainer 5561 (FIGS. 5-42-1 to5-42-6) is structured to adjustably interlock with a headgear buckle5560 (FIGS. 5-43-1 to 5-43-7). The tube retainer 5561 (e.g., constructedof plastic) is structured to retain at least two different sizedtubings, interface with the headgear buckle 5560, rotate within theheadgear buckle for desired positions for side sleeping,connect/disconnect from the headgear buckle, and does not allow tubeslide until a certain tube drag limit to avoid tube damage. Asillustrated, the tube retainer 5561 is generally round (e.g., circularor oval) with an opening 5561.1 at its proximal end. The air deliverytube may be passed through this opening 5561.1 via extension of the tuberetainer 5561. Slides or guiding surfaces 5561.2 may be placed on eitherside of the opening 5561.1 to aid in the positioning and/or insertion ofthe air delivery tube. Also, each of the inner radial arms or walls5561.3 of the tube retainer 5561 include multiple teeth 5561.4 (e.g., 3,4 or 5 teeth, or more or less) to better support the air delivery tubeonce clipped into the tube retainer 5561. In addition, one or more teeth5561.5 may be provided to support the air delivery tube. The arms orwalls 5561.3 of the tube retainer 5561 are structured to flex toaccommodate two or more different size tubings, e.g., short tube and 2 mair delivery tube (two different diameters), and do so over the lifetimeof the product.

The tube retainer 5561 has two buttons 5561.6 at its distal end that maybe resiliently pressed together to align the tongues 5561.7 together.Once aligned, the buttons 5561.6 may be engaged with the opening 5560.1on the headgear buckle 5560 by releasing the buttons 5561.6 and allowingthem to flex into the opening 5560.1. This mechanically locks the tuberetainer 5561 with the headgear buckle 5560, and allows the tuberetainer 5561 to rotate relative to the headgear buckle 5560. However,alternative methods of fixation may be used, e.g., buttons engaged withrespective grooves on the buckle, adhesives.

As illustrated, the headgear buckle 5560 includes opposing lockingportions 5560.2 adapted to be removably and adjustably coupled withrespective headgear straps, e.g., headgear strap may be wrapped aroundthe cross-bar of the associated locking portion in a known manner.

Also, the tube retainer 5561 may be rotated relative to the headgearbuckle 5560 to adjust its position. A detent assembly assists inrestraining the tube retainer 5561 at the desired position, and providestactile feedback with the motion of the tube retainer 5561.Specifically, the opening 5560.1 of the buckle 5560 includes detents5560.3 that interact with projections 5561.8 provided on each of thebuttons 5561.6 of the tube retainer 5561. In addition, the buckle 5560includes a series of recesses 5560.4 that interact with projections5561.9 provided on the underside of the tube retainer 5561. As the tuberetainer 5561 is rotated or adjusted, the projections 5561.8, 5561.9 ofthe tube retainer 5561 will move into and out of engagement withrespective detents 5560.3/recesses 5560.4 of the buckle 5560. Theprojections 5561.8, 5561.9 will be seated within respective detents5560.3/recesses 5560.4 to assist in restraining the tube retainer 5561at the desired position.

Alternative Tube Retainers and Buckles

FIGS. 5-48 to 5-86 illustrate tube retainers 7100 and headgear buckles7000 structured to manage tubing according to alternative embodiments ofthe present invention.

In each embodiment, the tube retainer is structured to stabilize the airdelivery tube increasing the opportunity for an effective seal to form.The stabilization of the air delivery tube will also enhance patientcomfort by allowing for a larger range of sleeping positions andreducing the incidence of irritation caused by tubing interference.

The tube retainer is a structure designed to maintain the air deliverytube in a fixed position. The tube retainer may be formed from anysemi-rigid or rigid material such as Hytrel, HTPC.

The buckle is a joining member between two headgear straps that allowsthe tension in the headgear to be adjusted (e.g., in the position ofheadgear buckle 60 shown in FIG. 1-1 or headgear buckle 5060 shown inFIG. 13-4). The buckle may be formed from any semi-rigid or rigidmaterial such as Hytrel, HTPC.

In the embodiments described below, each tube retainer 7100 (FIGS. 5-68to 5-86) may be connected to each buckle 7000 (FIGS. 5-48 to 5-67). Inan embodiment, each tube retainer 7100 may be easily and repeatedlyconnected to each buckle 7000. In an embodiment, each tube retainer 7100may be rotated, either fixed or freely, once connected to the buckle7000.

Buckle

As shown in FIGS. 5-48 to 5-67, each buckle 7000 includes two openingsor strap locks 7040 (e.g., laddered strap lock) for engagement withupper strap portions of the headgear (e.g., headgear strap may bewrapped around the cross-bar of the associated strap lock in a knownmanner) and a cutout section or keyhole 7060 in the center forengagement with a tube retainer.

In an embodiment, each buckle 7000 may have a height H, e.g., 2 mm, asshown in FIG. 5-48. This embodiment may be considered a low profilebuckle, which can be beneficial as it less obtrusive and morecomfortable for the patient. In FIG. 5-48, the buckle includes a cutout7090 along its outer edges on each side of the keyhole 7060. In anembodiment, such cutout 7090 may be more curved along its length asshown in FIG. 5-49, which soft curved edges increase comfort and add tothe visual appeal of the headgear.

Strap Locks

In an embodiment, the strap locks 7040 on the buckle 7000 may have acutout in the middle or anywhere along its longest side to form gap 7041and teeth 7042 as demonstrated in FIGS. 5-48 to 5-53. The gap 7041allows for easy engagement and disengagement of the upper strap portionsof the headgear. In an alternative embodiment, the teeth 7042 may havetapered tips 7043 to enable the headgear straps to slide more readilythrough gap 7041, as shown in FIG. 5-50. In yet another embodiment, theteeth 7042 may have tapered edges 7044 to enable the headgear straps toslide more readily through gap 7041, as shown in FIG. 5-51. The straplocks 7040 may also have a ladder-lock profile 7045 as shown in FIG.5-53.

Keyhole

The keyhole 7060 may be located in the center of the buckle 7000,however it may also be located at other suitable locations on thebuckle, e.g., offset from the center of the buckle.

The keyhole 7060 may have a general key shape as shown in FIG. 5-52.Alternatively, the keyhole 7060 may assume other suitable shapes, e.g.,generally circular shaped as shown in FIGS. 5-56 to 5-67. Inembodiments, the keyhole 7060 may have shaped (e.g., square, circular,triangular) apertures 7061 (e.g., 1, 2, 3, or more shaped apertures)extending from the keyhole 7060. In an embodiment, the apertures 7061may have a generally conical shape as shown in FIG. 5-66. Theseapertures 7061 can be evenly spaced (e.g., provided every 90°) orunevenly spaced. These apertures are to allow rotation and thusadjustment of the tube retainer when connected to the buckle. Thekeyhole 7060 may have a tapered entry 7062 as shown in FIG. 5-67.Tapered entry 7062 provides a lead-in for the tube retainer 7100 toensure correct alignment of tube retainer 7100 with buckle 7000.

The keyhole 7060 may also have one or more additional holes 7065 aboutthe keyhole 7060 as shown in FIGS. 5-54 to 5-63. In an embodiment, theadditional holes 7065 may follow the general path of the keyhole 7060(as shown in FIGS. 5-54 and 5-55) or the additional holes 7065 mayfollow a path unlike the keyhole 7060 (as shown in FIG. 5-56). Inembodiments, the additional holes 7065 may be substantially the samelength as keyhole 7060, longer than the keyhole 7060 (as shown in FIGS.5-56 and 5-63), or shorter than the keyhole 7060 (as shown in FIGS. 5-54and 5-55). The width of the additional holes 7065 may be relatively thin(e.g., 0.5 mm, see FIGS. 5-57 and 5-59) or relatively thick (e.g., 4 mm,see FIGS. 5-58 and 5-61) and the thickness may vary along its length. Inanother embodiment, the additional holes 7065 may vary in number, e.g.,there may be 1, 2, 3, 4, or more additional holes (see FIG. 5-59). Inyet another embodiment, the additional holes 7065 may adjoin keyhole7060 (as shown in FIGS. 5-56 to 5-59) or may be separated from keyhole7060 (as shown in FIGS. 5-54 and 5-55).

The additional holes 7065 are provided to allow spring or resilientflexibility during engagement of the tube retainer 7100 with the keyhole7060 and also during rotation of the tube retainer 7100 when engagedwith the keyhole 7060. Adjusting the length of holes 7065 will alter thespring properties and thus ease of engagement and disengagement and alsorotation of the tube retainer 7100 with the buckle 7000.

In an embodiment, a locking collar 7070 may be provided around keyhole7060 (see FIG. 5-60) or around the keyhole 7060 and additional holes7065 (see FIGS. 5-62 and 5-63). The locking collar 7070 may follow thepath of the keyhole 7060, as shown in FIGS. 5-60 and 5-65. The lockingcollar 7070 may extend around the entire perimeter of the keyhole 7060(see FIGS. 5-60 and 5-65) or may follow a portion or portions of thekeyhole 7060 (see FIG. 5-64). Locking bumps 7071 may be provided alongthe locking collar 7070 (shown in FIG. 5-60) to allow for fixed rotationof the tube retainer 7100 with respect to the buckle 7000 (e.g., detentassembly). The locking bumps 7071 may be generally hemispherical (asshown in FIG. 5-60), conical, or any other suitable shape. The number oflocking bumps 7071 may be varied (e.g., 3, 6, or other suitable number)to alter the number of fixed positions of the tube retainer 7100 withrespect to the buckle 7000.

Tube Retainer

As shown in FIGS. 5-68 to 5-82, each tube retainer 7100 has a generallyrounded curvature, an opening to allow a tube to pass through itscircumference, and a tab adapted to engage with a buckle 7000.

Arms

In the illustrated embodiments, each tube retainer 7100 has two arms7130 each with a generally rounded curvature. In an embodiment, the arms7130 may be generally circular as shown in FIG. 5-68 or may be generallyelliptical as shown in FIG. 5-69. In an alternative embodiment, the arms7130 may be irregularly shaped as shown in FIG. 5-70. Furthermore, thelower portion of the arms 7130 may be recessed to increase flexibility(e.g., see recessed portion 7131 shown in FIG. 5-71).

In an embodiment, a rib 7140 may be provided to the base of the arms7130 (as shown in FIGS. 5-69 to 5-74). In an embodiment, the rib 7140may be generally hemispherical or curved as shown in FIGS. 5-69, 5-71and 5-72. In an alternative embodiment, the rib 7140 may be generallyrectangular (or square) as shown in FIGS. 5-70 and 5-74. In anotherembodiment, the rib 7140 may be raised from the surface of arms 7130 asshown in FIG. 5-73 (e.g., T-shaped). The rib 7140 prevents the airdelivery tube from sliding erratically once engaged with tube retainer7100, meaning that the headgear and air delivery tube can be held in asecure position.

In an embodiment, the arms 7130 may have a locking mechanism 7135 thatoperates with a ball and clasp type joint (e.g., see FIGS. 5-72 to 5-75,5-77, and 5-78). As illustrated, the locking mechanism 7135 includes aball 7136 on one of the arms 7130 and a clasp 7137 on the other of thearms 7130. In use, the ball 7137 and clasp 7137 can be pushed togetherand interlocked to close the arms 7130 around the air delivery tube. Inan embodiment, the clasp 7137 may have one or more teeth 7137.1 on itsinner radius that are adapted to engage with respective grooves 7136.1on the ball 7136 as shown in FIG. 5-75. The teeth to grooves featurewill further secure and retain the locking mechanism 7135 in its lockingposition.

In another embodiment, the upper ends of the arms 7130 may include alead-in 7150 as shown in FIG. 5-76. The lead-in 7150 enables easierinsertion of the air delivery tube through the gap between the arms7130. The lead-in 7150 may also be combined with a locking mechanism7135 as shown in FIGS. 5-77 and 5-78. In FIG. 5-78, ribbing 7151 may beprovided to the under surface of each lead-in 7150. Ribbing 7151 enablesthe user to obtain a better grip when pulling the arms 7130 outward toremove the air delivery tube or when disengaging the locking mechanism7135. In yet another embodiment, teeth 7152 may be provided to the innersurface of the lead-in 7150 to contact the air delivery tube and providebetter stability of the air delivery tube, as shown in FIGS. 5-79 and5-80. The teeth 7152 may be generally square (as shown in FIG. 5-79),may be generally round (as shown in FIG. 5-80), may have other suitableshapes.

The inner radius of the arms 7130 may also be provided with one or moreribs 7131 as shown in FIG. 5-81. In use, the ribs 7131 provide supportfor the air delivery tube in the lateral direction. There may be anysuitable number of ribs 7131 (e.g., 2, 4, 7, or more) and these ribs maybe spaced evenly or randomly. The ribs 7131 may also vary in size, e.g.,the ribs may all be the same size or become longer to support differentshaped tubes.

Tab

In the illustrated embodiments, each tube retainer 7100 has a tab 7160at its base that is structured to engage with a keyhole 7060 provided tothe buckle 7000. FIGS. 5-68 to 5-86 show several embodiments of tab7160.

In an embodiment, the tab 7160 may be generally round as shown in FIG.5-76. In an alternative embodiment, the tab 7160 may assume othersuitable shapes, e.g., cross-like shape as shown in FIG. 5-82. Inanother form, the tab 7160 may have a fissure 7170 through its length(e.g., split configuration) as shown in FIG. 5-79. In anotherembodiment, the tab 7160 may include multiple fissures 7170 (e.g.,multiple prong arrangement). The fissure 7170 may be any suitable shape,e.g., square, circular or elliptical. The fissure 7170 is provided toadd flexion in tab 7160 to allow for easier engagement and disengagementwith the buckle keyhole 7060. The flexion in tab 7160 also provides asnapping sound when the tab 7160 is locked in the buckle keyhole 7060,which provides tactile feedback that the system is correctly aligned. Inanother embodiment, the tab 7160 may have a cut out 7161 through aportion of its length as shown in FIG. 5-86. In embodiments, there maybe one or more cut outs 7161 provided to the tab, e.g., 1, 2, 4, 7, orany other suitable number. The cut-out 7161 may be generally c-shaped orarcuate, or may have other suitable shapes. In use, the cut-out 7161enables greater flexibility of the tab 7160.

In yet another embodiment, the tab 7160 may have a lip 7165 extendingfrom its distal end as shown in FIG. 5-76. The lip 7165 is adapted tolock the tab 7160 in the buckle keyhole 7060 by an interference fit. Inan embodiment, the lip 7165 may extend around the entire perimeter ofthe distal end of tab 7160 (e.g., as shown in FIGS. 5-76 and 5-85). Inan alternative embodiment, the lip 7165 may extend around a portion orportions of the distal end of the tab 7160 (e.g., as shown in FIG.5-83). In another embodiment, the depth and length of the lip 7165 maybe varied. In an alternative embodiment, one or more finger tabs 7165.1may be provided to the tab that extend upwards from the topside of thelip 7165 (as shown in FIG. 5-84). In an embodiment, the finger tabs7165.1 may be generally rectangular, round, triangular, or any othersuitable shape. In use. the finger tabs 7165.1 allow fixed rotation ofthe tube retainer 7100 once engaged with the buckle 7000.

In an embodiment, the tab 7160 may also have a joining ridge 7166 at itsproximal end as shown in FIG. 5-76 (e.g., adjacent its interface withthe arms 7130). In an embodiment, the joining ridge 7166 may begenerally round but may have other suitable shapes. The joining ridge7166 is provided to ensure a snug fit of the tab 7160 with the bucklekeyhole 7060 so as to avoid lateral movement of the tube retainer 7100with respect to the buckle 7000. In an alternative embodiment, one ormore finger tabs 7166.1 may extend downwards from the underside of thejoining ridge 7166 as shown in FIG. 5-85. In an embodiment, the fingertabs 7166.1 may be generally rectangular, round, triangular, or anyother suitable shape. In use, the finger tabs 7166.1 allow fixedrotation of the tube retainer 7100 once engaged with buckle 7000.

Other alternatives to increase headgear flexibility to accommodatedifferent sleep positions includes: integrate tubing into headgearthrough conduit system; and/or introduce an elbow that accommodates awider range of movement through a ball and socket joint. The ball andsocket joint elbow may also provide decoupling of forces due to shiftsin tube position.

Other alternatives to increase decoupling of forces due to shifts intube position include: provide a tube that has increased levels offlexibility in the axial directions; interrupt tube with highly flexibleelement (i.e., thin silicone element) below elbow; provide a tube thatis constructed from an overall sifter material; and/or provide a tubethat is constructed from an overall more lightweight material.

2.6 Other Aspects

Headgear Cost Reduction

To reduce the cost of the headgear, the headgear may incorporate one ormore of the following: replace textile components with moldedcomponents; reduce part count for headgear; reduce materials used inheadgear; reduce labor involved in assembling headgear; increasemechanization of assembly process; and/or new material cutting profileto reduce wastage.

FIGS. 11-1 and 11-2 illustrate an exemplary cutting profile for headgearstraps to reduce wastage. In the illustrated embodiment, the headgearincludes two strap configurations, i.e., one for the side strap 53 andone for the rear strap 57. FIG. 11-1 illustrates a cutting profile forthe generally boomerang shaped side straps 53, and FIG. 11-2 illustratesa cutting profile for the generally straight rear strap 57. In eachembodiment, the straps are arranged side by side to reduce materialwastage.

Reducing Headgear Presence

Alternative embodiments to reduce the perceived presence of headgear(e.g., headgear made to feel more minimal/lightweight, provide minimalskin contact, and provide low intrusion into the field of view to reducethe likelihood of claustrophobia) include: providing a completelyelastic headgear strap design; reducing the overall amount of skincontact that the headgear has with the user; introducing a skin toned ortransparent headgear (e.g., chameleon headgear); eliminating all hardplastic components such as buckles and yokes; introducing cotton as theskin contact material (e.g., cotton may be better on skin and may bemore synonymous with clothing); using a cup or parachute materialsection to capture the crown (e.g., a net like section that may be madefrom cotton); reducing the overall material thickness of all parts ofthe headgear; using two or three thin (e.g., 1 mm) wire-style strips ofnylon to connect the frame to the headgear body (e.g., this arrangementmay accommodate fine adjustments and may have a very fine appearance onthe user, and this arrangement may be incorporated into a net styleheadgear which would appear almost invisible amongst the user's hair);eliminating the headgear and replacing its function with balloon stylepillows that inflate up against the walls of the nasal passage to holdthe pillows in place; and/or using an internal mouth guard which hasmagnets incorporated into it that will hold the pillow and frameassembly up against the upper lip and in position to retain a good seal(e.g., this arrangement may be incorporated with a balloon style prongsystem to completely eliminate the headgear).

Headgear Usability

Alternative embodiments to reduce the number/complexity of adjustmentsto achieve a correct fit/good seal include: introducing a single pieceheadgear that is highly flexible and provides sufficient breathability;introducing a highly flexible net style headgear system to capture thecrown; and/or eliminating buckles and introducing a headgear that uses asimpler series of adjustment mechanisms.

Alternative embodiments to improve the intuitiveness of headgearadjustment include: introducing a 3D shape headgear that provides anobvious visual cue as to the correct fitting of the headgear;positioning the adjustment mechanisms closer to the region influenced bythe adjustments (e.g., seal region) such that adjustments are moreintuitive; introducing Velcro tabs that provide a more intuitive methodof adjustment; and/or utilizing large Velcro tab sections as rigidizingelements to replace headgear yokes.

Alternative embodiments to improve the “set and forget” functionality ofheadgear (e.g., no need to reset/readjust after removal of headgear)include: incorporating a highly flexible element at points on theheadgear that allow stretching to be isolated to aid rapidremoval/replacement of headgear; and/or increasing the flexibility ofthe nasal pillows to accommodate the rapid removal/replacement ofheadgear.

Alternative embodiments to reduce the overall number of headgear partsinclude: providing single part headgear (e.g., textile or moldedheadgear); introducing Velcro tabs rather than having separate buckles;over-molding/insert molding the seal rings into the yokes; making theseal ring and yoke a single part; and/or utilizing large Velcro tabsections as rigidizing elements to replace the headgear yokes.

Alternative embodiments to improve ease of assembly/disassembly include:reducing overall number of parts; incorporating features that preventdisassembly (e.g., one time assembly); improving intuitiveness ofassembly and disassembly (e.g., through color coding or physicallocators/indicators); reducing the overall number of “open ends” (e.g.,eliminate back buckle); introducing 2-tone headgear (e.g., differentcolor on the inside surface to the outside surface which may reduceincidents of incorrect assembly in manufacturing; eliminating sealrings; and/or providing one-way assembly of headgear through headgearbuckles (e.g., restricted by geometry).

Alternative embodiments to improve ease of cleaning all surfacesinclude: reducing overall number of parts; making headgear suitable forthermal disinfection so that the interface does not have to becompletely disassembled to disinfect; and/or eliminating textileheadgear (e.g., replace textile headgear with an elastomeric orthermoplastic material that does not collect oil and moisture which mayallow the headgear to be wiped down as with other components of theinterface and may increase durability).

Alternative embodiments to increase the overall durability of headgearinclude: eliminating textile headgear (e.g., replace textile headgearwith an elastomeric or thermoplastic material that does not collect oiland moisture which may allow the headgear to be wiped down as with othercomponents of the interface and may increase durability); reducing theneed for adjustment; reducing the overall number of parts (e.g.,interfacing parts); and/or creating headgear straps out of a singlematerial structure rather than a laminated one (e.g., foam only headgearstraps).

Headgear Alternatives

FIGS. 12-1 to 12-26-2 illustrate headgear alternatives for the patientinterface. It should be appreciated that one or more features of any oneembodiment may be combinable with one or more features of the otherembodiments. In addition, any single feature or combination of featuresin any of the embodiments may constitute additional embodiments.

Mechanical Hinge

FIGS. 12-17 to 12-18-2 illustrate headgear with mechanical hinges. Suchhinges are structured to reduce or eliminate the influence of lateralforces on the seal region. In addition, lateral hinges may help toreduce or eliminate marking on the cheeks as the hinges allowaccommodation of users of varying facial widths and takes pressure offof the face.

In FIG. 12-17, the headgear includes headgear straps 3653 that cup thecrown of the patient's head (e.g., similar to that shown in WO2006/130903, which is incorporated herein by reference in its entirety),and yokes 3655 provided between the headgear straps 3653 and the nasalprong assembly. As illustrated, a lateral hinge 3695 is provided to anintermediate portion of the yoke 3655, e.g., offset to cheek region, toallow lateral movement of the yoke 3655 in use. A cheek pad 3690 (e.g.,high friction silicone cheek pad) is provided to the yoke 3655 adjacentthe hinge 3695 to support the hinge 3695 in a position off the patient'sface. In an embodiment, the cheek pad 3690 may be comolded or insertmolded to the yoke 3655. Also, the hinge 3695 may provide aquick-release function so that the hinge 3695 may be easily disconnectedand allow quick removal of the headgear. The combination of the headgearstrap arrangement and high friction silicone cheek pads may provide highlevels of overall stability for the headgear.

In FIG. 12-18-1, a lateral hinge 3795 is provided to either end portionof the yoke 3755 (e.g., at the nasal prong assembly 3720 and/or at theheadgear straps 3753) to allow lateral movement of the yoke 3755 in use.In the illustrated embodiment, the hinge 3795 is provided between thenasal prong assembly 3720 and the proximal end of the yoke 3755. A pad(not visible) is provided along the yoke 3755 to support the hinge 3795in a position off the patient's face. As shown in FIG. 12-18-2, the endof the frame of the nasal prong assembly 3720 provides dimples 3796 andan aperture 3797 for engaging an elbow or end plug. The proximal end ofthe yoke 3755 provides spaced apart arms 3798 that snap into respectivedimples 3796 on the end of frame to form the lateral hinge 3795. Also,the hinge 3795 may provide a quick-release function so that the hinge3795 may be easily disconnected and allow quick removal of the headgear.

Headgear Without “Dog Ear” Style Straps

FIGS. 12-22 to 12-25-2 illustrate headgear without “dog ear” stylestraps.

In FIG. 12-22, the headgear includes side strap portions 4153 (e.g.,constructed of Breathoprene), headgear yoke 4155 provided to the sidestrap portions, and upper and lower connecting strap portions 4157(U),4157(L) structured to connect the side strap portions. As illustrated,molded plastic crimps 4196 are positioned on ends of the side strapportions to engage respective ends of the connecting strap portions4157(U), 4157(L) and allow length adjustment. The connecting strapportions 4157(U), 4157(L) may include a highly flexible elastic elementto accommodate easy fitting/removal of the headgear. Also, the plasticcrimps 4196 are positioned to avoid pressing into the patient's head inthe most likely sleep positions, e.g., back and side of the head.

In FIGS. 12-23-1 and 12-23-2, the headgear includes side strap portions4253 (e.g., constructed of Breathoprene), and upper and lower connectingstrap portions 4257(U), 4257(L) structured to connect the side strapportions. As illustrated, molded plastic/silicone crimps 4296 arepositioned to engage the connecting strap portions and allow lengthadjustment. The connecting strap portions 4257(U), 4257(L) may include ahighly flexible elastic element to accommodate easy fitting/removal ofthe headgear. Also, the molded plastic/silicone crimps 4296 may bepositioned anywhere along the connecting strap portions to avoid thepatient's sleeping position, e.g., so patient does not lie on crimps.FIG. 12-23-1 illustrates one crimp 4296 provided to connect respectiveconnecting strap portions 4257(U), 4257(L), and FIG. 12-23-2 illustratestwo crimps 4296 provided to connect respective connecting strap portions4257(U), 4257(L). In an embodiment, the crimp may be in the form of ahinged c-clip that may be opened to adjust and closed to crimp, e.g.,such as that shown in FIG. 12-25-2.

In FIG. 12-24-1, the headgear includes side strap portions 4353 (e.g.,constructed of Breathoprene), and upper and lower connecting strapportions 4357(U), 4357(L) structured to connect the side strap portions.As illustrated, each end of a connecting strap portion includes atwo-part clip 4396 (e.g., constructed of plastic) adapted to engage aselected one of incremental holes 4397 provided along the side strapportions. As shown in FIGS. 12-24-2 and 12-14-3, each two-part clip 4396includes a top section 4396(1) that protrudes through the selected hole4397 in the strap portion and a bottom section 4396(2) that snaps ontothe top section 4396(1) (e.g., via prongs provided on the top section)to fasten the clip in place. The connecting strap portion 4357(U),4357(L) may be constructed of a highly flexible silicone/elastomericmaterial to accommodate easy fitting/removal of the headgear.

In FIG. 12-25-1, the headgear includes side strap portions 4453 (e.g.,constructed of Breathoprene), and upper and lower connecting strapportions 4457(U), 4457(L) structured to connect the side strap portions.As illustrated, a single piece living hinge component 4496 (e.g., moldedof plastic) is positioned on ends of the side strap portions to engagerespective ends of the connecting strap portions and allow lengthadjustment. As shown in FIG. 12-25-2, the living hinge component 4496provides first and second portions 4496(1), 4496(2) and a groove 4496(3)in each portion to receive the strap portions and crimp or clamp thestrap portions in place. The connecting strap portions 4457(U), 4457(L)may include a highly flexible elastic element to accommodate easyfitting/removal of the headgear (e.g., highly flexible elastic elementcan elastically deform to allow headgear removal).

Incremental Lateral Adjustment

In FIG. 12-26-1, the headgear includes headgear straps 4553 that cup thecrown of the patient's head, and yokes 4555 (e.g., silicone/moldedplastic yokes) provided between the headgear straps 4553 and the nasalprong assembly 4520. In this embodiment, each yoke 4555 may be adjustedby a “cam” style lock or ratchet mechanism 4575 that is incorporatedinto a molded plastic section 4576 on the side of the headgear straps4553. As shown in FIG. 12-26-2, the molded plastic section 4576 isstructured to receive a end portion of the yoke 4555 therethrough, andthe plastic section 4576 includes a locking arrangement to lock the endportion of the yoke in place. The locking arrangement includes a simplerelease button 4577 to release the yoke 4555. Also, the end portion ofthe yoke 4555 may have subtle ridges or teeth to provide tactilefeedback to the user on strap tension adjustment.

This embodiment provides increased levels of usability (e.g.,particularly during fitting and adjustment) for intuitive features suchas single piece 3D shaped headgear and lateral headgear tensionadjustments.

Alternative Headgear Embodiments to Improve Stability

Headgear stability may be improved by eliminating dislodging of theheadgear on the head and/or capturing the crown region of the head.

Exemplary headgear embodiments for improving stability include: provideadditional support around the head through a secondary strap which runsunder the ears; provide additional support around the head throughcapturing the crown region with different headgear geometry; provideadditional support around the head through one size fits all crown capor a single piece of material that sits over the crown of the head(e.g., may be perforated to allow breathing or take the form of a nettedsection of material, may also take the form of a two strap parachutestyle headgear); increase stability of headgear through theincorporation of a high friction material such as textured rubber ortextile (e.g., Velcro); increase stability through use of more siliconeparts against the skin as this has a high friction coefficient; and/oralter the way in which the headgear captures the crown, e.g., sitsfurther forward on the head and has a strap that runs along one plane tocapture the crown (this aids in clearance of the ear lobes, etc.).

Headgear Properties

Each headgear embodiment described above may include one or morefeatures to increase headgear fitting range, improve headgear comfort,reduce headgear cost, improve headgear aesthetics, and/or increaseprominence of branding.

For example, headgear embodiments may increase overall comfort byeliminating potential ergonomic hotspots, eliminating sources ofmarking/irritation, creating a lightweight feel, and/or maintaining highlevels of material breathability. Headgear embodiments may be designedin a manner that deviates from a “medical product” aesthetic butreflects a “lifestyle product” aesthetic, and creates a higher qualitylooking product overall. Also, headgear embodiments may incorporate andsupport more prominent branding through optimal branding locations andincreased differentiation of branding from the surrounding material.

Additional Embodiments

Additional embodiments may be generated by combining one or morefeatures of any one of the above-described embodiments with one or morefeatures of the other of the above-described embodiments. Suchadditional embodiments may include one or more of the followingfeatures:

Stability

-   -   Captures the crown region of the head sufficiently;    -   Decouples headgear forces well;    -   Accommodates different sleeping positions;    -   Good stability on the face (hugs the face and uses the structure        of the face for stability); and/or    -   Good stability of the headgear on the head (no slipping around).

Comfort

-   -   Reduce or eliminate irritation/marking on cheeks (swoosh marks);    -   Reduce or eliminate irritation caused by buckle;    -   Reduce or eliminate marking/irritation occurring on the upper        ear lobes; and/or    -   Good tactile quality (soft feel wherever possible).

Usability

-   -   Intuitive fitting;    -   Simple and quick adjustment;    -   Minimal number of adjustments to achieve a good fit;    -   Ability to make precision adjustments to maintain a good seal;    -   Set and forget functionality; and/or    -   Minimal number of parts.

Unobtrusiveness

-   -   Low perceived presence by the user (avoids the user's line of        sight);    -   Minimal overall size/visual impact of interface when on user;        and/or    -   Minimal skin contact and low likelihood of overheating the        patient or claustrophobia.

Aesthetics and Branding

-   -   Lifestyle product aesthetic (“non medical”);    -   Improved overall function through aesthetics (e.g., visual cues        for positioning and adjustment);    -   “High comfort” visual appearance;    -   Aesthetically pleasing and high quality user-product        relationship building features (e.g., customizable features,        colors, etc.);    -   Prominence of branding; and/or    -   High quality of branding.

Cleaning/Maintenance

-   -   Ease of assembly/disassembly (e.g., familiarity);    -   Ease of cleaning all surfaces (e.g., includes areas that do not        become clogged or trap dirt); and/or    -   Overall durability.        3 Connection with Air Supply        Elbow

As shown in FIGS. 18-1 to 18-7, the elbow 5040 (e.g., constructed of arelatively hard plastic material such as polypropylene, Hytrel, HTPC)includes a first portion 5042 provided to the frame 5030 and a secondportion 5044 provided to a short tube 5070 (e.g., see FIGS. 14-1 and 17)adapted to be connected to an air delivery tube.

The elbow 5040 is structured to provide easy assembly/disassembly to theframe, rotation with respect to the frame with acceptable level oftorque, seal, and venting. In addition, the elbow directs air into thepatient interface without significant flow restrictions.

In an embodiment of the elbow (see FIGS. 18-1 to 18-7), D1 may be about15-20 mm, e.g., 17.99 mm, D2 may be about 10-20 mm, e.g., 15 mm, D3 maybe about 5-10 mm, e.g., 7.8 mm, D4 may be about 5-15 mm, e.g., 9.6 mm,and D5 may be about 10-15 mm, e.g., 13.5 mm. Although specificdimensions and ranges are indicated, it is to be understood that thesedimensions and ranges are merely exemplary and other dimensions andranges are possible depending on application. For example, the exemplarydimensions may vary by 10-20% or more or less depending on application.

As illustrated, the second portion 5044 tapers to a smaller internaldiameter at D5 (e.g., about 13.5 mm), e.g., for sealing the lip 5075.1of the tube against surface 5048 (e.g., see FIG. 17). Moreover, gaspasses from a smaller diameter at D5 (e.g., about 13.5 mm) to a largerdiameter at D2 (e.g., about 15 mm), which reduces the pressure dropthrough the elbow to maintain a sufficient impedance level.

In the illustrated embodiment, the first portion 5042 is angled about90° with respect to the second portion 5044. This arrangement provides alow profile in use, e.g., 90° elbow and attached tubing does not stickoutwardly when rotated, reduces mask size. In addition, the 90° elbowprovides a quieter venting arrangement and is easier to tool/manufacturewith a 90° flat blank at the surface for the vent hole pins. However,the first and second portions of the elbow may have other suitableangles with respect to one another, e.g., 120°. In an alternativeembodiment, the elbow may include one or more baffles along itsinterior.

Frame Attachment

The first portion 5042 of the elbow 5040 includes a tapered retainingportion 5043.1, a circumferential flange 5043.2, and a circumferentialrib 5043.3 between the retaining portion 5043.1 and the flange 5043.2.The first portion 5042 is engageable with the tube portion 5035 of theframe 5030. The tube portion 5035 include an inwardly facingcircumferential rib 5035.1 at an inner end and an inwardly facingcircumferential sealing lip 5035.2 at an outer end (e.g., see FIGS.15-10 and 15-11).

The first portion 5042 of the elbow 5040 is inserted into the tubeportion 5035 of the frame 5030 and the retaining portion 5043.1 engagesthe rib 5035.1 with a snap-fit (relatively hard elbow snaps intorelatively soft frame). That is, the retaining portion 5043.1 deformsand compresses the rib 5035.1 inwardly until the retaining portion5043.1 reaches its operative position in which the rib 5035.1 springsback to original form, as shown in FIG. 17. As illustrated, the sealinglip 5035.2 of the frame 5030 provides a seal around the perimeter of thefirst portion 5042 and/or the sloped surface of portion 5043.2 of theelbow 5040. Because the frame provides a relatively soft part to engagethe relatively hard elbow, no additional seal ring is needed to sealbetween the frame and elbow.

The circumferential flange 5043.2 and circumferential rib 5043.3 (rib5043.3 may be optional) provided to the elbow 5040 help prevent rotationof the elbow 5040 relative to the frame (e.g., prevents rocking orwiggle and keeps elbow and frame concentric). In an embodiment, thecircumferential rib 5043.3 may be spaced apart ribs (rather thancontinuous) to reduce friction.

In the illustrated embodiment, a small clearance may be provided betweenthe circumferential flange 5043.2 and the edge of the opening into theinternal volume of the frame, e.g., only contact points are the sealinglip 5035.2 with the elbow and the retaining portion 5043.1 with theframe. Thus, the insertion length of the elbow into the frame is aboutthe length of D4 (e.g., about 9-11 mm (e.g., 9.6 mm)), which providessufficient length to securely retain the elbow to the frame. Inaddition, the elbow does not engage the frame along its entire length,so less friction is provided between the elbow and the frame. In anembodiment, the ratio of the insertion length (D4) to the related elbowdiameter (D2) may be about 50-75%, e.g., 9.6/15 or about 65%.

Also, the sealing lip 5035.1 is angled towards the inlet of the frameopening and engages a lower end of the circumferential flange 5043.2, asshown in FIG. 17. This arrangement allows the sealing lip 5035.1 tomaintain a seal with the elbow 5040, e.g., when tube drag or other forceapplied to elbow causes bending movement of the first portion withrespect to the frame. For example, as the elbow pivots with respect tothe frame due to an external force, the sealing lip 5035.1 resilientlymaintains contact with the tapered surface of the circumferential flange5043.2.

However, it should be appreciated that the elbow 5040 may be attached tothe frame 5030 in other suitable arrangements, e.g., ball joint.

FIGS. 18-9-1 to 18-18-3 illustrate elbow to frame attachments accordingto alternative embodiments of the present invention.

FIGS. 18-9-1 to 18-9-3 illustrate an elbow 7340 attached to the frame7330 by a ball and socket type joint. In the illustrated embodiment, theball 7345 is provided to the elbow 7340 and the socket 7335 is providedto the frame 7330. However, it should be appreciated that the oppositearrangement is possible, i.e., socket on elbow and ball on frame.

As illustrated, the socket 7335 on frame 7330 provides a generallyrounded inwardly facing surface, and the ball 7345 on elbow 7340 has agenerally rounded or spherical outwardly facing surface adapted toengage the socket 7335 with an interference fit.

Also, the frame 7330 provides a channel 7333 structured to retain thenasal prong assembly, and the main body of the elbow 7340 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7328 for gas washout. In theillustrated embodiment, the vent holes 7328 are arranged in a generallycircular or arcuate manner. However, other suitable hole arrangements,hole numbers, and/or hole shapes on the elbow are possible.

FIGS. 18-10-1 to 18-10-3 illustrate a relatively soft elbow 7440 (e.g.,relatively semi-rigid or soft plastic material (e.g., hard silicone(e.g., 30-80 shore A silicone))) attached to a frame 7430. Asillustrated, the frame 7430 includes a tube portion 7435 with a rib7435.1 and an inwardly facing sealing surface 7435.2. The elbow 7440includes a retaining portion 7443.1 adapted to engage the rib 7435.1(e.g., with a snap fit) and a sealing end portion 7443.2 adapted toengage the sealing surface 7435.2 to provide a seal. Also, the elbow7440 includes a flange 7443.3 adapted to engage the end face of the tubeportion 7435. Because the elbow provides a relatively soft part toengage the frame, no additional seal ring is provided to seal betweenthe frame and elbow.

Also, the frame 7430 provides a channel 7433 structured to retain thenasal prong assembly, and the main body of the elbow 7440 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7428 for gas washout. In theillustrated embodiment, the vent holes 7428 are arranged in a generallycircular or arcuate manner. However, other suitable hole arrangements,hole numbers, and/or hole shapes on the elbow are possible.

FIGS. 18-11-1 to 18-11-3 illustrate a relatively soft elbow 7540attached to a frame 7530 and to a relatively hard swivel 7560. Asillustrated, the frame 7530 includes a tube portion 7535 with a rib7535.1 and an inwardly facing sealing surface 7535.2. One end of theelbow 7540 includes a retaining portion 7543.1 adapted to engage the rib7535.1 (e.g., with a snap fit) and a sealing end portion 7543.2 adaptedto engage the sealing surface 7535.2 to provide a seal. Also, the elbow7540 includes a flange 7543.3 adapted to engage the end face of the tubeportion 7535.

The swivel 7560 includes a rib 7565.1 and an inwardly facing sealingsurface 7565.2. The other end of the elbow 7540 includes a retainingportion 7545.1 adapted to engage the rib 7565.1 (e.g., with a snap fit)and a sealing end portion 7545.2 adapted to engage the sealing surface7565.2 to provide a seal. Also, the elbow 7540 includes a flange 7545.3adapted to engage the end face of the swivel 7560.

Because the elbow provides a relatively soft part to engage the frameand swivel, no additional seal ring is provided to seal between theframe and elbow or between the swivel and elbow.

Also, the frame 7530 provides a channel 7533 structured to retain thenasal prong assembly, and the main body of the elbow 7540 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7528 for gas washout. In theillustrated embodiment, the vent holes 7528 are arranged in a generallycircular manner (e.g., concentric circles). However, other suitable holearrangements, hole numbers, and/or hole shapes on the elbow arepossible.

FIGS. 18-12-1 to 18-12-3 illustrate a relatively hard elbow 7640 with aseal ring attached to a frame 7630. As illustrated, the frame 7630includes a tube portion 7635 with a shoulder 7635.1. The elbow 7640includes a retaining portion 7643.1 adapted to engage the shoulder7635.1 (e.g., with a snap fit). A slot 7641 is provided to opposingsides of the elbow 7640 to facilitate deflection during its snap-fitattachment.

Also, the frame 7630 provides a channel 7633 structured to retain thenasal prong assembly, and the main body of the elbow 7640 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7628 for gas washout. In theillustrated embodiment, the vent holes 7628 are arranged in a generallycircular or arcuate manner. However, other suitable hole arrangements,hole numbers, and/or hole shapes on the elbow are possible.

FIGS. 18-13-1 to 18-13-3 illustrate a relatively soft elbow 7740attached to a frame 7730 with a relatively large frame bore. Asillustrated, the frame 7730 includes a tube portion 7735 with a rib7735.1. The elbow 7740 includes a retaining portion 7743.1 adapted toengage the rib 7735.1 (e.g., with a snap fit). Also, the elbow 7740includes a flange 7743.3 adapted to engage the end face of the tubeportion 7735.

Also, the frame 7730 provides a channel 7733 structured to retain thenasal prong assembly, and the main body of the elbow 7740 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7728 for gas washout. In theillustrated embodiment, the vent holes 7728 are arranged in offset rows(e.g., six offset rows). However, other suitable hole arrangements, holenumbers, and/or hole shapes on the elbow are possible.

In addition, the elbow 7740 includes a baffle 7750 that is arranged todivide the upper arm of the elbow into an air delivery passage and anexhaust passage. As illustrated, the baffle has a wavy or w-shapedconfiguration. However, other baffle shapes are possible.

FIGS. 18-14-1 to 18-14-3 illustrate a relatively soft elbow 7840attached to a frame 7830 with a large frame bore. As illustrated, theframe 7830 includes a tube portion 7835 with a rib 7835.1. The elbow7840 includes a retaining portion 7843.1 adapted to engage the rib7835.1 (e.g., with a snap fit). Also, the elbow 7840 includes a flange7843.3 adapted to engage the end face of the tube portion 7835.

Also, the frame 7830 provides a channel 7833 structured to retain thenasal prong assembly, and the main body of the elbow 7840 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7828 for gas washout. In theillustrated embodiment, the vent holes 7828 are arranged in offset rows(e.g., three offset rows). However, other suitable hole arrangements,hole numbers, and/or hole shapes on the elbow are possible.

In addition, the elbow 7840 includes a baffle 7850 that is arranged todivide the upper arm of the elbow into an air delivery passage and anexhaust passage. As illustrated, the baffle has a generally flat orplanar configuration. However, other baffle shapes are possible.

FIGS. 18-15-1 to 18-15-3 illustrate an elbow 7940 attached to a frame7930 with a large frame bore. As illustrated, the frame 7930 includes atube portion 7935 with a rib 7935.1. The elbow 7940 includes a retainingportion 7943.1 adapted to engage the rib 7935.1 (e.g., with a snap fit).Also, the elbow 7940 includes a flange 7943.3 adapted to engage the endface of the tube portion 7935.

Also, the frame 7930 provides a channel 7933 structured to retain thenasal prong assembly, and the main body of the elbow 7940 includes arelatively flat portion for a vent arrangement. The vent arrangementincludes a plurality of vent holes 7928 for gas washout. In theillustrated embodiment, the vent holes 7928 are arranged in an arc andeach vent hole includes a generally oval or capsule shape. However,other suitable hole arrangements, hole numbers, and/or hole shapes onthe elbow are possible.

In addition, the elbow 7940 includes a baffle 7950 that is arranged todivide the upper arm of the elbow into an air delivery passage and anexhaust passage. As illustrated, the baffle has a generally inverseU-shaped configuration. However, other baffle shapes are possible.

FIGS. 18-16-1 to 18-16-3 illustrate an elbow to frame attachment similarto that shown in FIGS. 18-15-1 to 18-15-3 and indicated with similarreference numerals. In contrast, the vent holes 7928 are arranged in anarc with a larger radius of curvature, and the baffle 7950 has a largerradius of curvature (i.e., similar to the vent hole arc).

FIGS. 18-17-1 to 18-17-3 illustrate an elbow to frame attachment similarto that shown in FIGS. 18-15-1 to 18-15-3 and indicated with similarreference numerals. In contrast, each vent hole 7928 has a generalU-shape and the vent holes are arranged on a flat portion that isrecessed with respect to the exterior surface of the elbow. In addition,the baffle 7950 has a generally U-shaped configuration.

FIGS. 18-18-1 to 18-18-3 illustrate an elbow to frame attachment similarto that shown in FIGS. 18-15-1 to 18-15-3 and indicated with similarreference numerals. In contrast, the vent holes 7928 are arranged inoffset columns and arranged on a flat portion that is recessed withrespect to the exterior surface of the elbow. In addition, the baffle7950 has a generally U-shaped configuration.

Vent Arrangement

A vent arrangement 5045 is positioned on a relatively flat portion ofthe elbow 5040. As illustrated, the relatively flat portion has agenerally circular shape.

In the illustrated embodiment, the vent arrangement 5045 includes aplurality of holes 5047 arranged in concentric rings, e.g., threeconcentric rings R1, R2, R3. As shown in FIGS. 18-1, 18-2, and 18-7, thecenter ring R1 includes 3-10 holes, e.g., 6 holes, the intermediate ringR2 includes 5-30 holes, e.g., 14 holes, and the outside ring R3 includes5-50 holes, e.g., 22 holes.

In the illustrated embodiment, each hole 5047 may have a generally partconic shape, including opposed walls that converge from a larger(inside) diameter to a smaller (outside) diameter, as viewed in thedirection of exhausted gas (see FIGS. 18-5 and 18-6). In an embodiment,the maximum length of each hole 5047 may be about 2.5 mm, and thesmaller outside diameter may be about 0.7 mm with a 5° draft angle.

However, it should be appreciated that the vent arrangement 5045 mayinclude other suitable hole arrangements, hole numbers, and/or holeshapes.

Also, as shown in FIGS. 18-4, 18-5, and 18-7, the elbow provides roundededges along its interior surface in order to reduce noise at the cornersof the elbow. Such arrangement may result in the vent holes of theoutside ring R3 being longer than the vent holes of the center andintermediate rings R1, R2 (e.g., see FIG. 18-6).

Elbow with Alternative Vent Arrangement

FIGS. 18-8-1 to 18-8-15 illustrate an elbow 5740 (e.g., constructed ofpolypropylene) according to another embodiment of the present invention.As illustrated, the first portion 5742 is angled about 90-130°, e.g.,105° with respect to the second portion 5744. In addition, the first andsecond end portions 5742, 5744 provide an alternative structure forengaging the frame and short tube respectively.

The vent arrangement 5745 is positioned on a relatively flat portion ofthe elbow 5740 and includes a plurality of holes 5747 arranged in offsetrows. As shown in FIGS. 18-8-5 and 18-8-8, the arrangement 5745 mayinclude 1-15 rows, e.g., 9 rows, with each row including 3-10 holes,e.g., 5, 6, or 7 holes. In an embodiment, the vent arrangement mayinclude 40-70 total holes, e.g., 53 holes.

In the illustrated embodiment, each hole 5747 may have a generally partconic shape, including opposed walls that converge from a larger(inside) diameter to a smaller (outside) diameter, as viewed in thedirection of exhausted gas (see FIGS. 18-8-11, 18-8-13, and 18-8-15). Inan embodiment, the smaller outside diameter D1 may be about 0.6 mm witha draft angle D2 of about 5°. Edges of the larger (inside) diameter maybe rounded, e.g., inlet radius D4 about 0.25-0.5 mm (e.g., 0.34 mm).

In this embodiment, each vent hole 5747 includes a diameter (about 0.6mm) that is smaller than the diameter of each vent hole for ResMed'sSwift II mask (about 0.7 mm). Thus, in comparison to ResMed's Swift IImask, each vent hole 5747 provides a smaller venting area (ventingarea=number of holes×area of each hole), less vent flow, and a smallerpitch (distance between holes).

As shown in FIGS. 18-8-10, 18-8-12, and 18-8-14, tooling for the elbow5740 provides a smooth inner path, e.g., the elbow includes roundededges along its interior surface, e.g., in order to reduce noise. Sucharrangement may result in outer vent holes being longer than inner ventholes, e.g., length D5 may be about 2-3 mm (e.g., 2.47 mm) and length D6may be about 1.5-2.5 mm (e.g., 1.81 mm) as shown in FIG. 18-8-13. InFIG. 18-8-11, the vent holes along the vertical axis have a length D3 ofabout 1.5-2.5 mm, e.g., 1.7 mm.

However, it should be appreciated that the vent arrangement 5745 mayinclude other suitable hole arrangements, hole numbers, hole sizes,and/or hole shapes.

The elbow 5740 is structured to provide an interface between the frameand the short tube assembly (e.g., see FIGS. 20-5-1 to 20-5-6). Ventingof the mask system is provided by the array of small vent holes 5747located in the elbow with a constant exhaust direction regardless of theelbow rotation position. The elbow decouples twisting forces from tubingto the frame by providing a 360 degree rotation with the frame. Thisrotation (in conjunction with the optional tube retainer) also allowsthe user to position the short tube and air delivery tubing in apreferred location for sleeping. The elbow to frame interface ensuresthat the elbow remains connected during use and allows the user toquickly assemble and disassemble tubing during the night and for easycleaning.

The elbow includes one or more of the following functions: to provide ameans of attaching tubing to the frame; to provide adequate area for avent (due to limited space on the rest of the patient interface); toprovide a total vent flow (in conjunction with the rest of the masksystem) for safe use and flow generator compatibility; to provide animpedance (in conjunction with the rest of the mask system) withinspecification of ResMed's “Mirage” flow generator curve setting; toprovide adequate CO₂ washout performance (in conjunction with the restof the mask system); to provide adjustment of the tube position through360 degree rotation; to provide a system of decoupling tube drag forcesthrough rotation and/or swiveling actions; to provide easy assembly anddisassembly with the mask; to provide adequate vent noise performance;to provide a vent direction that does not adversely affect the comfortof the patient or bed partner; to allow the user to easily clean themask; to be unobtrusive and both visually and physically minimal inorder to avoid the user feeling stifled or claustrophobic; and/or to beaesthetically pleasing and reflect high quality and style.

In an embodiment, the total flow specification for the patient interfaceof FIGS. 22-23-1 to 22-23-6 may be lower than the flow specification forResMed's Swift II mask (e.g., minimum flow curve at 4 cmH2O to 20 cmH2Oabout 75% of Swift II nominal flow curve). The advantages of having alower flow specification are reduced mask noise and reduced discomfortof jetting air inside the user's nose. In an embodiment, the length ofthe elbow inlet is sufficiently long to provide time for the flow tobecome laminar.

In the illustrated embodiment, the vent arrangement 5745 is located onthe elbow 5740. Alternatively, vents may be located at other suitablelocations, e.g., on the frame, short tube, etc. In the illustratedembodiment, the vent design consists of an array of 53 holes of nominaldiameter of 0.6 mm to provide adequate vent flow.

Features of the vent arrangement will now be described in greaterdetail. The vent pin blankoff provides a flat surface with about 75°blankoff. The elbow angle of 105° improves aesthetics and optimizesrange of tubing positioning. The 105° elbow may also be quieter than a120° elbow, for example. The flat surface for blankoff minimizes toolingrisk, tool life/maintenance and flash.

The smaller vent hole size of Ø0.6 mm produces less noise and providesacceptable CO₂ performance with humidification maintained.

The vent hole draft (i.e., converging vent hole with 5° included draft)produce less noise.

The vent hole inlet radius of about 0.34 mm is larger (than ResMed'sSwift II, about 0.25 mm) for less noise (e.g., maximum possible betweenholes).

The vent hole length may range from about 1.7 mm for inner holes to 2.5mm for outer holes. A longer vent hole length is provided for lessnoise. The hole length varies, e.g., due to the curvature of the elbow,e.g., curvature provided for a smoother internal wall transition betweenthe inlet and outlet which produces less noise.

As shown in FIG. 18-8-8, the vent hole spacing includes D7 of about 1.45mm and D8 of about 0.70 mm. The spacing between centers of about 1.45 mmcorresponds to a minimum distance of approximately 0.7 mm between thetangency lines of the inlet radii, e.g., for tooling.

In an embodiment, the vent hole diameter, draft, inlet radius, lengthand spacing may be sized to fit in required space.

The internal elbow geometry provides an internal wall transition betweenthe inlet and outlet that is relatively smooth. The smoother internalwall transition between the inlet and outlet produces less noise. Asillustrated, the internal curvature is gradual while still maintainingan acceptable hole length for the outer holes due to the flat blank-offsurface area.

The low mask noise of the patient interface may be achieved through oneor more of the following features: lower flow specification (reducedflow means reduced noise); smaller vent hole diameter of Ø0.6 mm;increased vent hole length (for the outer holes) and larger inletradius; elbow internal transition between inlet and outlet as gradual aspossible; close spacing (high concentration) of vent holes leads tointeraction between adjacent jets that reduces the noise; negligibleleak in the rest of the patient interface which contributes to overallmask noise.

In an embodiment, the vent arrangement has a sound power of about 25 dBA(e.g., also due to the lower flow at the same pressure), which issignificantly quieter than vents known in the art (e.g., ResMed's SwiftII (28-29 dBA), Opus (31 dBA), OptiLife (34 dBA)).

As shown in FIG. 18-8-16, the vent direction of the elbow 5740 is in thesame direction as ResMed's Swift II mask (indicated by darker portionS2). The vent direction does not change with elbow rotation but is fixedin an axial direction. The 30 degree angle between the nasal prongassembly to frame interface and the prong to patient interface enables avent direction equivalent to ResMed's Swift II mask to be achieved.Also, minor adjustments to the vent direction are possible by adjustingthe yoke-to-frame orientation (the prong to patient seal can bemaintained due to the flexibility in the nasal prong assembly).

The smaller vent hole diameter and the lower flow specification assistsin minimizing jetting. Also, because the vent exhausts in a narrow beam,the jetting is confined to a smaller area and therefore potentially lesslikely to affect (or more easily managed by) the patient or bed partner.

The elbow design has been structured to suit the impedance requirementsof the ResMed's “Mirage” flow curve. Matching the impedancecharacteristics in this way assists with ensuring compatibility withResMed flow generators. However, it should be appreciated that the elbowmay be used with other suitable flow generators.

FIG. 18-8-16 shows the elbow 5740 attached to the frame 6030 and nasalprong assembly 6020 described above. In the illustrated embodiment, theelbow to frame interface is a continuous annular snap fit between apolypropylene elbow and a silicone frame (70-75 Shore A durometer). Thishard-to-soft type interface has a number of advantages with respect tothe elbow-to-frame interface as detailed below.

When the elbow is assembled to the frame a thin silicone lip 6035.2(thickness of 0.3 to 0.4 mm or less) is deflected creating aninterference seal with the elbow sealing surface 5741. The amount ofinterference is determined by both the axial stackup to the retentionfeature and the diametrical stackup. This interface effectively providesa zero leak interface under static operating conditions. The amount ofinterference has been designed to accommodate some tube drag.

The retention of the elbow to the frame is important to ensure that theshort tube assembly does not inadvertently disconnect during use. A 10Ntube drag load was considered to be sufficient retention force in alldirections, e.g., at this force the mask seal to the patient is brokenand likely to be completely clear of the face. The retention of theelbow is provided by a snap engagement of 0.7 mm all around thecircumference. A 60 degree return angle A1 on the elbow barb 5743.1 wasimplemented to assist disassembly by the user while maintainingsufficient retention.

Assembly and disassembly should be easy enough to be performed by atypical user with limited dexterity considering the small size of theparts. Assembly of the elbow to the frame is assisted with a 30 degreesinsertion angle A2 on the elbow barb 5743.1. The intent was to have anaxial assembly force under about 40N. Subjectively assembly is actuallyeasier as the user is more likely to manipulate the elbow into positionwith some angle or twist and this requires less force. Elbow disassemblyis linked with elbow retention however disassembly is realisticallyeasier than the retention force as the user can peel the elbow out withmuch less force.

The elbow can rotate 360 degrees within the frame to provide flexibilityin tube positions and decouple tube drag forces during sleep movement.Due to the hard-to-soft interference for sealing of the elbow to frame,some rotational resistance may be provided. Some resistance may bepreferable over freely rotating as the tube can be located in a certaindirection without it inadvertently swinging around and disturbing thewearer. Factors influencing the rotation torque include the sealing lipinterference, the sealing lip thickness, and/or the silicone framehardness.

Sufficient clearance elsewhere in the interface (e.g., between the elbowflange 5749 and frame 6030) was ensured across tolerance ranges toensure minimal contact and torque contribution. Clearance is controlledto some extent to minimize movement of the elbow within the frame thatmay lead to leakage under a tube drag load.

In an embodiment, the elbow rotation torque specification is less than30Nmm and subjectively is considered to be acceptable if the short tubecan rotate under its own weight.

FIG. 18-8-17 shows the interface between the elbow 5740 and the shorttube 5770, e.g., barbed, friction-type fit. The short tube material,e.g., made of Hytrel 5556, provides greater flexibility and durabilityand has a much higher thermal resistance enabling thermal disinfectionat higher temperatures. The elbow/short tube interface may have othersuitable arrangements, e.g., snap fit, swivel fit, etc.

The 105 degree angle elbow includes one or more of the followingadvantages: reduces the chance of the short tube impacting on thepatient's chest while ensuring that the tube can be angled back farenough to route the tubing over the head; less noise; less obtrusive.

Wall thickness variation of the elbow was minimized however, somethicker wall sections were implemented to improve the aesthetics andunobtrusiveness of the elbow. The circular groove in the elbow flange5749 was implemented to remove material bulk from this area of theelbow, improve molding quality, and/or dimensional control.

Short Tube and Swivel

The short tube 5070 is adapted to interconnect the patient interfacewith a standard air delivery tube (e.g., 22 mm tube). As shown in FIGS.14-1 and 20-1, the short tube 5070 includes a tube portion 5072 and endfittings 5074 provided to respective ends of the tube portion 5072. Theend fittings 5074 include the same structure, with one of the endfittings 5074 attachable to the second portion of the elbow 5040 and theother of the end fittings attachable to a swivel 5090 adapted to beconnected to an air delivery tube. Such arrangement facilitates assemblyand disassembly (e.g., for cleaning, disinfecting, etc.), provides aseal to reduce leak, and provides a limited number of parts to reduceassembly/disassembly steps.

The tube portion 5072 (e.g., 13-15 mm inner diameter (e.g., 13.5 mminner diameter)) may have a reduced length (e.g., 30-40 mm (e.g., 35mm)) to reduce impedance. Also, the width, height, pitch, and/or helicalrib of the tube portion 5072 may be adjusted to adjust the flexibilityof the short tube. For example, the size of the pitch of the helixaround the tube portion may be adjusted to adjust the flexibility.

End Fittings

Each end fitting 5074 (e.g., constructed of a semi-rigid material suchas TPE, silicone) may be integrally formed in one piece with the tubeportion 5072 (e.g., constructed of a hard plastic material (e.g., 45-55shore D hardness) such as polypropylene, PTE, Dupont Hybrid, Hytrel,Ritaflex, opaque ribs, translucent film, or combinations thereof) or maybe formed separately from the tube portion 5072 and attached thereto(e.g., glued, welded). In an embodiment, the end fittings 5074 may beovermolded to respective ends of the tube portion 5072.

As best shown in FIGS. 20-2 and 20-4, each end fitting 5074 includes asealing lip 5075.1 at its free end, an annular flange 5075.2 thatprovides a snap feature, and one or more annular ribs 5075.3 (e.g., tworibs) that provide finger grips.

Swivel Attachment

The swivel 5090 (e.g., constructed of a hard plastic material such aspolypropylene, Hytrel, HTPC) includes a first portion 5092 adapted toconnect to the short tube 5070 and second portion 5094 adapted toconnect to an air delivery tube.

As shown in FIGS. 20-2 to 20-4, the first portion 5092 providesdiametrically opposed windows 5095.1 through the swivel side wall and aninwardly facing tapered surface 5095.2. The second end portion 5094provides a tapered side wall for connection to the air delivery tube.Also, spaced apart flanges 5096 are provided to the swivel 5090 whichdefines a space therebetween for a tube retainer clip adapted to retainthe air delivery tube.

The end fitting 5074 of the short tube 5070 is structured to engage thefirst portion 5092 of the swivel 5090 with a snap or press fit, i.e.,annular flange 5075.2 resiliently deflects into windows 5095.1. Inaddition, the sealing lip 5075.1 of the end fitting 5074 resilientlydeflects into engagement with the inwardly facing tapered surface 5095.2to provide an interference fit for sealing around the interior perimeterof the swivel. The first portion 5092 of the swivel 5090 also includescut outs 5098 (see FIGS. 20-2 and 20-3) to provide finger clearance tofacilitate assembly/disassembly of the end fitting 5074 to the swivel5090.

In an alternative embodiment, the swivel may be overmolded to an endfitting of the short tube, e.g., to reduce the number of components,size, etc. In other alternatives, the swivel may be bonded with glue orwelded to the end fitting.

Elbow Attachment

The other of the end fittings 5074 of the short tube 5070 is attachableto the elbow 5040 in a similar manner as the swivel 5090. Specifically,as shown in FIG. 17, the end fitting 5074 of the short tube 5070 isstructured to engage the second portion 5044 of the elbow 5040 with asnap fit, i.e., annular flange 5075.2 resiliently deflects into windows5046 (see FIGS. 18-1 and 18-3). In addition, the sealing lip 5075.1 ofthe end fitting 5074 resiliently deflects into engagement with theinwardly facing tapered surface 5048 to provide an interference fit forsealing around the interior perimeter of the elbow. The second portion5044 of the elbow 5040 also includes cut outs 5049 (see FIGS. 18-1 and18-3) to provide finger clearance to facilitate assembly/disassembly ofthe end fitting 5074 to the elbow 5040.

FIGS. 20-5-1 to 20-5-6 illustrate a short tube 5770 with elbow 5740 andswivel 5790 according to another embodiment of the present invention.The elbow 5740 (described above in reference to FIGS. 18-8-1 to 18-8-7)and swivel 5790 may be attached to respective ends of the short tube5770, e.g., by friction fit, mechanical interlock, and/or overmolding.In the illustrated embodiment, a small bore tube adaptor 5791 isprovided to the short tube for coupling the swivel 5790, e.g., adaptorprovides barbed connection.

The short tube includes one or more of the following functions: connectsthe air supply to the patient interface from the flow generator withinan acceptable level of impedance level as specified by systemrequirement; reduces forces that may de-stabilize the mask and sealingbecause of the tube drag that weight of the flow generator tube andtangling of this tube may cause; reduces visual and physicalobtrusiveness of the overall mask size; the inside of the tube is smoothto minimize generating noise due to air turbulence; the stiffness of thetube shall be sufficient to prevent kinking or stretched under normalusage conditions; tube fittings shall not have any smell; the tube shallhave thermal insulation properties to reduce condensation build-up or“raining” in the tube; aesthetically pleasing and reflect high qualityand style; the tube should be easy to assemble/disassemble from themask; total leak in the short tube assembly should not cause the totalmask flow to be outside the specified flow limit; the tube end fittingshould have a finger grip area, an area that can hold on to duringassembly and disassembly of the tube from the elbow or from the swivel.

In an embodiment, the length of the tube is about 200-400 mm, e.g., 300mm, the elbow to tube retention is more than about 20N, and the swivelto tube retention is more than about 20N.

The short tube may also include one or more of the following features:

Through Impedance: The through impedance characteristics in the shorttube assembly (e.g., short tube and end fittings or connectors) shouldnot cause the mask system impedance to be elevated above acceptablelimits. The length and the diameter of the short tube, surface finishinside the connectors and in the short tube, the shape of the elbowfitting, and amount of change in flow direction may be contributingfactors that affect the through impedance in the short tube assembly. Inaddition, the position of the airflow inlet in relation to the nasalprong assembly may contribute to the airflow impedance.

Kinking and Occlusion: The short tube may be sufficiently rigid orconstructed to minimize the possibility of kinking when placed over thetop of bedrails or through the top of doors of incubators. The shorttube may be structured to prevent occlusion when placed in areas aroundthe patient, including when the patient's head or arm is on the shorttube. The resistance to kinking and occlusion of the short tube can bebased on the material strength of the short tube, the thickness of theshort tube walls and the ribs, and the short tube dimensions such as thelength, the pitch distance of the helix, and the diameter of the shorttube.

Flexibility of the Short Tube: The short tube should be sufficientlyflexible to reduce any forces applied to the mask system during anymovement of the air tubes. Movement of the short tube towards differentelbow positions should not cause extra leakage between the nasal prongsand nasal cavity.

Leakage in the Short Tube Assembly: In an embodiment, the leakage in theshort tube assembly is less than 1 L/min @ 20 cmH₂O.

Tube Retention: In an embodiment, the short tube assembly is structuredto withstand 30 cmH₂O of pressure for about 12 hours without dislodgmentof parts, and the connection of the parts is structured to withstand 20N of pull force at various angles without fracturing or detaching fromthe mask elbow (force limit is about double the maximum bearable forcewhich could be applied to person's face).

Swivel Rotational Requirements: The purpose of the swivel is to reduceapplication of any torsion forces to the mask system when the patientchanges sleeping positions. The swivel can rotate through 360 degreesrelative to the tube adaptor or lower swivel. In an embodiment, theswivel will not squeak during normal movement of the short tube or themask system. In an embodiment, the swivel may securely snap-fit onto thelower swivel.

Comfort Factor: The short tube may be structured to optimize comfortwhen the patient moves during sleep. For example, all the parts in theshort tube assembly may have a substantially smooth finish on its outersurface.

Assembly Integrity: In an embodiment, the short tube assembly does nothave parts that are likely to catch bedclothes and dislodge the masksystem or interrupt the seal.

Biocompatibility: In an embodiment, all short tube components arebiocompatible.

Chemical Human Factors: In an embodiment, the tube assembly is easy toassemble and disassemble. For example, the components may be intuitiveto assemble and disassemble, and may be fail safe (only able to beassembled in one way) if ends of the short tube assembly have differentconnection.

Dislodging: The mask system may be structured so that small parts cannotdislodge and be inhaled.

Durability During Use: The short tube assembly (including mask) may bedurable or disposable.

In an embodiment, the short tube may have a diameter of about 13-13.5 mm(e.g., 13.5 mm) and a length of about 200-250 mm (e.g., 250 mm).However, other dimensions are possible as noted above.

The short tube may be manufactured from Polyolefin (e.g., which allowsthe tube to be made transparent), Hytrel (e.g., Hytrel 5556), orRiteflex materials. In an embodiment, the short tube and connectors maybe made from a combination of Hytrel or Riteflex material to allowovermolding of the short tube on the connectors.

4 Other Aspects

Patient Interface

FIGS. 1-1 and 2-1 to 2-2 illustrate a patient interface or mask systemaccording to an embodiment of the present invention. As illustrated, thepatient interface includes a nasal prong assembly 20 (FIGS. 2-1 to 2-2)adapted to provide an effective seal or interface with the patient'snose and headgear 50 (FIG. 1-1) adapted to support the patient interfacein a desired position on the patient's head.

Comfort and Seal

Embodiments of the invention are directed towards patient interfaceshaving structure to provide a comfortable and effective seal with thepatient's face. Moreover, embodiments of the invention are directedtowards patient interfaces having improved static sealing performance(e.g., the ability to allow lower strap tension from headgear to createa sealing force) and improved dynamic sealing performance (e.g., theability to withstand macro-movement from a patient rolling around in bedand maintain a seal and/or to withstand changes in the patient's face inthe short term (when the face relaxes and the cheeks fill willpressurized air) and in the long term (if the patient's facial featureschange, e.g., based on weight change, etc.). For example, embodiments ofthe invention are directed towards patient interfaces having one or morefeatures that, either alone or in cooperation with other features,provide a unit that as a whole allows a range of movement withoutbreaking seal or losing comfort (e.g., patient can sleep on side withoutdislodging nasal prongs from the patient's nose). Such interfaceproperties are described in greater detail below.

Alternative Patient Interface Embodiment

FIGS. 13-1 to 13-4 and 14-1 to 14-2 illustrate a patient interface ormask system 5010 according to another embodiment of the presentinvention. As illustrated, the patient interface 5010 includes a frame5030, a nasal prong assembly 5020 provided to the frame 5030 and adaptedto provide an effective seal or interface with the patient's nose, anelbow 5040 provided to the frame 5030 and adapted to be connected to anair delivery tube that delivers breathable gas to the patient, andheadgear 5050 adapted to support the patient interface in a desiredposition on the patient's head. As illustrated, the patient interfaceprovides a relatively narrow configuration with a central swivel whichprovides a comfortable interface that allows a range of movement in use(described in greater detail below).

Comfort, Seal, and Allowing Range of Sleeping Positions

As illustrated, the patient interface 5010 provides an arrangementincluding a low number of components, a relatively small overall sizeincluding a relatively small, narrow frame (smaller profile,streamlined, less obtrusive), no seal rings, end caps, or vent caps,relatively thin headgear yokes with reduced obtrusiveness (e.g., lessvisual obtrusion), easy assembly, enhanced adjustability, andperceivable to be light and small. In addition, the patient interface5010 provides an arrangement that may be more comfortable for sidesleepers and may even allow the patient to be face down whilemaintaining a seal. For example, the patient interface 5010 allows arange of movement without breaking seal or loosing comfort (e.g.,patient can sleep on side without dislodging nasal prongs from thepatient's nose).

In an embodiment, as shown in FIGS. 13-2 and 13-4, the patient interfacemay include a width W (i.e., width of nasal prong assembly) of about50-60 mm, e.g., 54 mm, a height H (i.e., height from tip of nasal prongto bottom of elbow) of about 65-75 mm, e.g., 69 mm, and a depth D (i.e.,depth from edge of nasal prong assembly to edge of elbow) of about 35-45mm, e.g., 39 mm. These dimensions are merely exemplary, and otherdimension are possible depending on application.

Alternative Systems for Positioning and Supporting Nasal Prongs

FIGS. 31-1 to 45-2 illustrate alternative systems for positioning andsupporting a pair of nasal prongs in a patient's nares for the provisionof respiratory treatment, e.g., CPAP treatment. Aspects of the inventionrelate to reducing or minimizing the size of such a system.

For example, in an embodiment, ResMed's Swift mask may be reduced inwidth by relocating tube lugs on the frame to the inside of the frame,the elbow may be shortened, a seal ring may be added to the port plug orelbow (e.g., o-ring), and the yokes may be connected directly to theframe.

FIGS. 31-1 and 31-2 illustrate a mask system 9510 in which the yoke toframe interface 9585 is extended from the yoke 9555 and connected to anarrowed frame/nasal prong assembly 9520. As illustrated, a side tubeexit is provided, e.g., to reduce the risk of seal compromise throughtube drag.

FIGS. 32-1 and 32-2 illustrate another mask system 9610 in which theyoke to frame interface 9685 is extended from the yoke 9655 andconnected to a narrowed frame 9630 and nasal prong assembly 9620. Asillustrated, a side tube exit is provided, e.g., to reduce the risk ofseal compromise through tube drag. In this embodiment, the yoke 9655 andframe 9630 may be integrally molded as a one piece structure or may bemolded as two separate pieces.

FIGS. 33-1 and 33-2 illustrate a mask system 9710 in which nasal prongassembly 9720 is supported by a cradle 9759 provided to the yokes 9755.Such cradle arrangement reduces mask width by shifting rotationalsupport from the ends of the nasal prong assembly (two locations) to thecenter of the nasal prong assembly (single location).

FIG. 34 illustrates a mask system 9810 in which a Y-piece inlet tube9870 is provided to the mask for central mounting. The side tube exitson the mask may reduce the risk of seal compromise through tube drag.Such inlet tube may be used with the yoke to frame interfaces shown inFIGS. 32-1 to 33-2.

FIG. 35 illustrates a mask system 9910 in which a simple plastic frame9930 supports or holds silicone molded prongs 9924 provided to an inlettube 9970, e.g., prongs inserted through and retained within openingsprovided to frame. Such arrangement provides a mask system with low partcount.

FIG. 36 illustrates a mask system 10010 in which a silicone nasal prongassembly 10020 includes an angular adjustment built into or integratedinto the assembly. For example, the nasal prong assembly 10020 mayinclude pins 10021 received in respective openings of the yokes 10055,e.g., friction fit. A cavity 10023 in respective sides of the nasalprong assembly 10020 allow for a degree of rotation.

FIG. 37 illustrates a mask system 10110 in which a silicone nasal prongassembly 10120 is wrapped around a rigid plastic tube 10130. The rigidtube 10130 acts as an air path and two holes 10131 in the rigid tuberelease pressurized air to the nasal prong assembly 10120. Sucharrangement provides a reduction in parts and a reduction in mask width.

FIG. 38 illustrates a mask system 10210 including a rigid inner tube10230, a flexible silicone outer frame 10231 provided to the tube 10230,and nasal prongs 10224 engaged or pushed into the rigid inner tube10230. A side tube exit is provided, e.g., to reduce the risk of sealcompromise through tube drag.

FIGS. 39-1 and 39-2 illustrate a mask system 10310 including a simpleplastic frame 10330 that supports or holds a silicone molded pronginterface 10320. As illustrated, the prong interface 10320 includes pins10321 received in respective openings of the frame 10330, e.g., with afriction fit. Also, the prong interface 10320 includes a tube portion13023 adapted to engage an inlet tube 10370. The frame 10330 includesopenings for engaging respective headgear straps and may act as arigidizer to headgear straps. Such arrangement provides a mask systemwith a minimalist design including a low part count and small/narrowfootprint.

FIG. 40 illustrates a nasal prong 10424 that is free to rotate ortranslate along a curved path within a secondary rigid component 10440.Such prong arrangement may be integrated into one or more of theembodiments described above. In an embodiment, each nasal prong may beindependently rotated or otherwise adjusted with respect to thesecondary rigid component 10440.

In another embodiment, the nasal prong assembly may be reduced in width.For example, FIG. 41-1 illustrates a nasal prong assembly 10520 having awidth W and FIG. 41-2 illustrates a nasal prong assembly 10620 having awidth w which is about 40% less than that of nasal prong assembly 10520.As shown in FIG. 41-3, the nasal prong assembly 10620 may be secured inposition by wrapping each end 10621 of the nasal prong assembly over alip 10631 on the frame 10630 and then engaging the yoke 10655 over theend 10621.

FIG. 42 illustrates a mask system 10710 without a frame. As illustrated,ends of the nasal prong assembly 10720 (e.g., one piece arrangement) areretained by the yoke 10755 which also supports the elbow 10740.

FIG. 43 illustrates nasal prongs 10824 push-fit to a frame 10830. In anembodiment, overmolded seal rings 10858 may be provided to ends of theframe 10830.

FIG. 44 illustrates another embodiment of a mask system 10910 without aframe. As illustrated, ends of the nasal prong assembly 10920 wraparound the yokes 10955 to seal. The nasal prong assembly 10920 may selfseal or a clip may provided to facilitate a seal. The elbow or shorttube 10940 may be sealed to the yoke 10955 via an o-ring 10941 (e.g.,overmolded to the elbow). In the illustrated embodiment, each side ofthe mask includes an inlet port (i.e., double sided port) in which oneside may be blocked off. Alternatively, only one side of the mask mayinclude a port (i.e., single sided port), therefore no plug may benecessary. The side mounted elbow-to-yoke arrangement may improvestability of the mask, e.g., compared to a front mountedelbow-to-frame/nasal prong assembly arrangement.

FIG. 45-1 illustrates a nasal prong assembly 11020 having a central axisA and FIG. 45-2 illustrates a nasal prong assembly 11120 having acentral axis a which is shifted to make the prongs longer in the nose toreduce width. This arrangement may also improve comfort by lifting theprongs off the patient's top lip in use. In an embodiment, the masksystem may be provided without a frame so that the yokes 11155 supportthe nasal prong assembly 11120.

Range of Movement

In an embodiment, the patient interface may be broadly broken down intoa pair of nasal prongs adapted to provide an effective seal or interfacewith the patient's nose and a support arrangement to support the nasalprongs in an operative position on the patient's face. The supportarrangement is structured to provide a range of rotational, axial, andlateral movement to the nasal prongs while maintaining a sufficient sealand resisting the application of tube drag and headgear tension to thenasal prongs. In an embodiment, the support arrangement may includeeverything besides the nasal prongs and even parts of the nasal prongs,e.g., a gusset, a frame, and/or headgear as described above. Thus, thepatient interface provides one or more features that, either alone or incooperation, allow a range of movement without breaking seal or loosingcomfort.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.In addition, while the invention has particular application to patientswho suffer from OSA, it is to be appreciated that patients who sufferfrom other illnesses (e.g., congestive heart failure, diabetes, morbidobesity, stroke, bariatric surgery, etc.) can derive benefit from theabove teachings. Moreover, the above teachings have applicability withpatients and non-patients alike in non-medical applications.

What is claimed is:
 1. A patient interface for delivering breathable gasto a patient, the patient interface comprising: a nasal prong assemblyincluding a pair of nasal prongs structured to sealingly communicatewith nasal passages of a patient's nose in use; and headgear to maintainthe nasal prong assembly in a desired position on the patient's face,the headgear including first and second side straps and respectiverigidizers provided to respective side straps such that each of therespective rigidizers is coextensive with a respective side strap atleast along a portion of the headgear configured to extend along a sideof the patient's bead, each of the respective rigidizers providingrigidity to a respective one of the first and second side straps, eachrigidizer including a first end portion that provides 1) a connectorstructured to engage a respective end of the nasal prong, assembly and2) a protrusion that curves inwardly of the connector and forms a cheeksupport, the cheek support adapted to follow a contour of the patient'scheek and guide a respective end portion of the side strap intoengagement with the patient's cheek to provide a stable cheek support.2. A patient interface according to claim 1, wherein the patientinterface further comprises a base region and each nasal prong includesa head portion adapted to seal with a respective patient nasal passageand as stalk that interconnects the head portion with the base region.3. A patient interface according to claim 2, wherein the bead portionincludes a. dual or double-wall arrangement including an inner wall andan outer wall that surrounds the inner wall.
 4. A patient interfaceaccording to claim 2, wherein each prong includes an uppertrampoline-like suspension system between the head portion and thestalk, and a lower trampoline-like suspension system between the stalkand the base region.
 5. A patient interface according, to claim 1,wherein the nasal prong assembly includes structure to reduce and/oreliminate an air jetting effect.
 6. A patient interface according toclaim 1, wherein the cheek support is arranged such that headgeartension is applied to the cheek support rather than to the pair of nasalprongs to prevent the pair of nasal prongs from being compressed.
 7. Apatient interlace according to claim 1, wherein each of the respectiverigidizers includes rib-strengthened brackets to support the connectoron the rigidizer.
 8. A patient interlace according to claim 1, whereinthe headgear includes a rear strap that passes around a rear portion ofthe patient's head.
 9. A patient interface according to claim 8, whereineach of the respective rigidizers includes a slot that defines across-bar adapted to engage a respective end of the rear strap.
 10. Apatient interface according to claim 1, wherein each of the respectiverigidizers is attachable to a respective side strap via stitching,welding, and/or gluing.
 11. A patient interface according, to claim 1,wherein a width of the side strap on at least one side of the rigidizeris about 5-9 mm.
 12. A patient interface for delivering breathable gasto a patient, the patient interface comprising: a nasal seal tosealingly communicate with the patient's nose in use and headgear tomaintain the nasal seal in position on the patient's face, the headgearincluding side portions, each of said side portions including a sidestrap and a rigidizer provided to the side strap, each rigidizerincluding a main portion and a curved protrusion branching off from themain portion and terminating in a free end, the curved protrusionthereby forming a cheek support configured to Mow a contour of thepatient's cheek and guide an end portion of each respective side strapinto engagement with the patient's cheek to provide a stable cheeksupport, wherein the cheek support is configured to flex relative to themain portion in order to conform to the contours of the patient's cheek.13. A patient interface for delivering breathable gas to a patient, thepatient interface comprising: a nasal prong assembly including a pair ofnasal prongs structured to sealingly communicate with nasal passages ofa patient's nose in use; a frame configured to support the pair of nasalprongs; and headgear connectable to the frame to maintain the frame andthe nasal prong assembly in position on the patient's face, the headgearincluding left and right side straps formed of soft, flexible materialand respective rigidizers formed of semi-rigid material attached to therespective left and right side straps to provide rigidity to the leftand right side straps, wherein each of said respective rigidizersincludes a main portion and an end portion, the end portion branchingoff from the main portion in two directions to form. respectively, 1) aconnector configured to connect the rigidizer to a respective end of theframe and 2) a flexible cheek support terminating in a free end andbeing configured to disperse headgear tension across the patient's cheeksuch that headgear tension is applied to the flexible cheek supportinstead of the nasal prongs.
 14. A patient interface according to claim13, wherein each flexible cheek support is configured to follow thecontour of the patient's cheek and guide a respective end portion of theside strap into engagement with the patient's cheek.
 15. A patientinterface according to claim 13, wherein each flexible cheek support isconfigured to disperse headgear tension below the patient's cheek bone.16. A patient interface according to claim 13, wherein each flexiblecheek support extends from the respective rigidizer as a cantilever. 17.A patient interface according to claim 13, wherein the left and rightside straps are elastic.
 18. A patient interface according to claim 13,wherein the frame comprises an aperture between the respective ends ofthe frame that is configured to receive a flow of breathable gas.
 19. Apatient interface according to claim 13, wherein each connector issupported on the respective rigidizer by brackets.
 20. A patientinterface according to claim 19, wherein the brackets comprise ribs thatincrease rigidity of the connector.
 21. A patient interface according toclaim 19, wherein the flexible cheek support is provided between thebrackets.
 22. A patient interface according to claim 1, wherein eachrigidizer includes a second end portion connected to a main portion ofthe rigidizer.
 23. A patient interface according to claim 22, whereinboth the first and second end portions are located at opposing ends ofthe respective rigidzer.
 24. A patient interface according to claim 23,wherein the second end portion is configured to be connected to a strap.25. A patient interface according to claim 12, wherein the protrusioncurves inwardly from the side strap toward a front of the patient'sface.
 26. A patient interface according to claim 25, wherein a connectorbranches off from the main portion of each rigidizer and is configuredto connect the riuidizer to a frame which supports the nasal.
 27. Apatient interface according to claim 13, wherein the flexible cheeksupport terminates at a location away from the main portion of therigidizer.
 28. A patient interface according to claim 1, furthercomprising a pad provided to each of the respective rigidizers andadapted to contact a side of the patient's face, wherein the padincludes foam.
 29. A patient interface according to claim 12, furthercomprising a pad provided to the rigidizer and adapted to contact a sideof the patient's face, wherein the pad includes foam.
 30. A patientinterface according to claim 12, wherein each rinidizer is coextensivewith the respective side strap at least along a portion of the headgearconfigured to extend along a side of the patient's head, the rigidizersproviding rigidity to the first and second side straps.
 31. A patientinterface according to claim 13, further comprising a pad provided toeach of the respective rigidizers and adapted to contact a. side of thepatient's face, wherein the pad includes foam.
 32. A patient interfaceaccording to claim 13, wherein each rigidizer is coextensive with arespective side strap at least along a portion of the headgearconfigured to extend along a side of the patient's head.
 33. A patientinterface according to claim 12, wherein the free end of the curvedprotrusion is configured to be positioned on the patient's cheek whenthe patient interlace is worn.
 34. A patient interface according toclaim 13, wherein the free end of the flexible cheek support isconfigured to he positioned on the patient's cheek when the patientinterface is worn.